From a0926d9ef08e8abdb611c5e7e4de2593af3f8fc1 Mon Sep 17 00:00:00 2001
From: Jiminy Panoz <JayPanoz@users.noreply.github.com>
Date: Wed, 8 Jul 2026 16:13:54 +0200
Subject: [PATCH 1/7] Init fixtures

First pass with help of agents being provided existing docs. Needs to be reviewed.
---
 demo/playground/index.html                    |   63 +
 demo/playground/script.js                     |  166 ++
 demo/playground/styles.css                    |  226 +++
 fixtures/README.md                            |  165 ++
 fixtures/ROLES_COVERAGE.md                    |   76 +
 fixtures/abstract-epub-type/gnd.json          |    6 +
 fixtures/abstract-epub-type/input.html        |   11 +
 fixtures/abstract-epub-type/meta.json         |   10 +
 fixtures/abstract-epub-type/utterances.json   |    5 +
 fixtures/abstract-role-aria/gnd.json          |    6 +
 fixtures/abstract-role-aria/input.html        |    1 +
 fixtures/abstract-role-aria/meta.json         |   10 +
 fixtures/abstract-role-aria/utterances.json   |    5 +
 fixtures/acknowledgments-epub-type/gnd.json   |    6 +
 fixtures/acknowledgments-epub-type/input.html |   11 +
 fixtures/acknowledgments-epub-type/meta.json  |   10 +
 .../acknowledgments-epub-type/utterances.json |    5 +
 fixtures/acknowledgments-role-aria/gnd.json   |    6 +
 fixtures/acknowledgments-role-aria/input.html |    1 +
 fixtures/acknowledgments-role-aria/meta.json  |   10 +
 .../acknowledgments-role-aria/utterances.json |    5 +
 fixtures/afterword-epub-type/gnd.json         |    6 +
 fixtures/afterword-epub-type/input.html       |   11 +
 fixtures/afterword-epub-type/meta.json        |   10 +
 fixtures/afterword-epub-type/utterances.json  |    5 +
 fixtures/afterword-role-aria/gnd.json         |    6 +
 fixtures/afterword-role-aria/input.html       |    1 +
 fixtures/afterword-role-aria/meta.json        |   10 +
 fixtures/afterword-role-aria/utterances.json  |    5 +
 fixtures/appendix-epub-type/gnd.json          |    6 +
 fixtures/appendix-epub-type/input.html        |   11 +
 fixtures/appendix-epub-type/meta.json         |   10 +
 fixtures/appendix-epub-type/utterances.json   |    5 +
 fixtures/appendix-role-aria/gnd.json          |    6 +
 fixtures/appendix-role-aria/input.html        |    1 +
 fixtures/appendix-role-aria/meta.json         |   10 +
 fixtures/appendix-role-aria/utterances.json   |    5 +
 fixtures/article-html-native/gnd.json         |    6 +
 fixtures/article-html-native/input.html       |    1 +
 fixtures/article-html-native/meta.json        |   10 +
 fixtures/article-html-native/utterances.json  |    5 +
 fixtures/aside-html-native/gnd.json           |    6 +
 fixtures/aside-html-native/input.html         |    1 +
 fixtures/aside-html-native/meta.json          |   10 +
 fixtures/aside-html-native/utterances.json    |    5 +
 fixtures/audio-html-native/gnd.json           |    7 +
 fixtures/audio-html-native/input.html         |    1 +
 fixtures/audio-html-native/meta.json          |   10 +
 fixtures/audio-html-native/utterances.json    |    5 +
 fixtures/backlink-epub-type/gnd.json          |    7 +
 fixtures/backlink-epub-type/input.html        |   11 +
 fixtures/backlink-epub-type/meta.json         |   10 +
 fixtures/backlink-epub-type/utterances.json   |    5 +
 fixtures/backlink-role-aria/gnd.json          |    7 +
 fixtures/backlink-role-aria/input.html        |    1 +
 fixtures/backlink-role-aria/meta.json         |   10 +
 fixtures/backlink-role-aria/utterances.json   |    5 +
 fixtures/bibliography-epub-type/gnd.json      |   26 +
 fixtures/bibliography-epub-type/input.html    |   16 +
 fixtures/bibliography-epub-type/meta.json     |   12 +
 .../bibliography-epub-type/utterances.json    |    8 +
 fixtures/bibliography-role-aria/gnd.json      |   26 +
 fixtures/bibliography-role-aria/input.html    |    6 +
 fixtures/bibliography-role-aria/meta.json     |   12 +
 .../bibliography-role-aria/utterances.json    |    8 +
 fixtures/biblioref-epub-type/gnd.json         |    7 +
 fixtures/biblioref-epub-type/input.html       |   11 +
 fixtures/biblioref-epub-type/meta.json        |   10 +
 fixtures/biblioref-epub-type/utterances.json  |    5 +
 fixtures/biblioref-role-aria/gnd.json         |    7 +
 fixtures/biblioref-role-aria/input.html       |    1 +
 fixtures/biblioref-role-aria/meta.json        |   10 +
 fixtures/biblioref-role-aria/utterances.json  |    5 +
 fixtures/blockquote-html-native/gnd.json      |    6 +
 fixtures/blockquote-html-native/input.html    |    1 +
 fixtures/blockquote-html-native/meta.json     |   10 +
 .../blockquote-html-native/utterances.json    |    5 +
 fixtures/body-html-native/gnd.json            |    6 +
 fixtures/body-html-native/input.html          |    1 +
 fixtures/body-html-native/meta.json           |   10 +
 fixtures/body-html-native/utterances.json     |    5 +
 fixtures/chapter-epub-type/gnd.json           |   13 +
 fixtures/chapter-epub-type/input.html         |   13 +
 fixtures/chapter-epub-type/meta.json          |   11 +
 fixtures/chapter-epub-type/utterances.json    |    5 +
 fixtures/chapter-role-aria/gnd.json           |   13 +
 fixtures/chapter-role-aria/input.html         |    3 +
 fixtures/chapter-role-aria/meta.json          |   11 +
 fixtures/chapter-role-aria/utterances.json    |    5 +
 fixtures/colophon-epub-type/gnd.json          |    6 +
 fixtures/colophon-epub-type/input.html        |   11 +
 fixtures/colophon-epub-type/meta.json         |   10 +
 fixtures/colophon-epub-type/utterances.json   |    5 +
 fixtures/colophon-role-aria/gnd.json          |    6 +
 fixtures/colophon-role-aria/input.html        |    1 +
 fixtures/colophon-role-aria/meta.json         |   10 +
 fixtures/colophon-role-aria/utterances.json   |    5 +
 fixtures/complementary-role-aria/gnd.json     |    6 +
 fixtures/complementary-role-aria/input.html   |    1 +
 fixtures/complementary-role-aria/meta.json    |   10 +
 .../complementary-role-aria/utterances.json   |    5 +
 fixtures/conclusion-epub-type/gnd.json        |    6 +
 fixtures/conclusion-epub-type/input.html      |   11 +
 fixtures/conclusion-epub-type/meta.json       |   10 +
 fixtures/conclusion-epub-type/utterances.json |    5 +
 fixtures/conclusion-role-aria/gnd.json        |    6 +
 fixtures/conclusion-role-aria/input.html      |    1 +
 fixtures/conclusion-role-aria/meta.json       |   10 +
 fixtures/conclusion-role-aria/utterances.json |    5 +
 fixtures/cover-epub-type/gnd.json             |   14 +
 fixtures/cover-epub-type/input.html           |   13 +
 fixtures/cover-epub-type/meta.json            |   10 +
 fixtures/cover-epub-type/utterances.json      |    5 +
 fixtures/cover-role-aria/gnd.json             |    7 +
 fixtures/cover-role-aria/input.html           |    1 +
 fixtures/cover-role-aria/meta.json            |   10 +
 fixtures/cover-role-aria/utterances.json      |    5 +
 fixtures/credit-epub-type/gnd.json            |    6 +
 fixtures/credit-epub-type/input.html          |   11 +
 fixtures/credit-epub-type/meta.json           |   10 +
 fixtures/credit-epub-type/utterances.json     |    5 +
 fixtures/credit-role-aria/gnd.json            |    6 +
 fixtures/credit-role-aria/input.html          |    1 +
 fixtures/credit-role-aria/meta.json           |   10 +
 fixtures/credit-role-aria/utterances.json     |    5 +
 fixtures/credits-epub-type/gnd.json           |   40 +
 fixtures/credits-epub-type/input.html         |   16 +
 fixtures/credits-epub-type/meta.json          |   13 +
 fixtures/credits-epub-type/utterances.json    |    8 +
 fixtures/credits-role-aria/gnd.json           |   40 +
 fixtures/credits-role-aria/input.html         |    6 +
 fixtures/credits-role-aria/meta.json          |   13 +
 fixtures/credits-role-aria/utterances.json    |    8 +
 fixtures/dedication-epub-type/gnd.json        |    6 +
 fixtures/dedication-epub-type/input.html      |   11 +
 fixtures/dedication-epub-type/meta.json       |   10 +
 fixtures/dedication-epub-type/utterances.json |    5 +
 fixtures/dedication-role-aria/gnd.json        |    6 +
 fixtures/dedication-role-aria/input.html      |    1 +
 fixtures/dedication-role-aria/meta.json       |   10 +
 fixtures/dedication-role-aria/utterances.json |    5 +
 fixtures/definition-epub-type/gnd.json        |   13 +
 fixtures/definition-epub-type/input.html      |   13 +
 fixtures/definition-epub-type/meta.json       |   11 +
 fixtures/definition-epub-type/utterances.json |    5 +
 fixtures/definition-html-native/gnd.json      |    6 +
 fixtures/definition-html-native/input.html    |    3 +
 fixtures/definition-html-native/meta.json     |   10 +
 .../definition-html-native/utterances.json    |    5 +
 fixtures/definition-role-aria/gnd.json        |    6 +
 fixtures/definition-role-aria/input.html      |    1 +
 fixtures/definition-role-aria/meta.json       |   10 +
 fixtures/definition-role-aria/utterances.json |    5 +
 fixtures/details-html-native/gnd.json         |    6 +
 fixtures/details-html-native/input.html       |    1 +
 fixtures/details-html-native/meta.json        |   10 +
 fixtures/details-html-native/utterances.json  |    5 +
 fixtures/endnotes-epub-type/gnd.json          |   42 +
 fixtures/endnotes-epub-type/input.html        |   16 +
 fixtures/endnotes-epub-type/meta.json         |   13 +
 fixtures/endnotes-epub-type/utterances.json   |    8 +
 fixtures/endnotes-role-aria/gnd.json          |   42 +
 fixtures/endnotes-role-aria/input.html        |    6 +
 fixtures/endnotes-role-aria/meta.json         |   13 +
 fixtures/endnotes-role-aria/utterances.json   |    8 +
 fixtures/epigraph-epub-type/gnd.json          |    6 +
 fixtures/epigraph-epub-type/input.html        |   11 +
 fixtures/epigraph-epub-type/meta.json         |   10 +
 fixtures/epigraph-epub-type/utterances.json   |    5 +
 fixtures/epigraph-role-aria/gnd.json          |    6 +
 fixtures/epigraph-role-aria/input.html        |    1 +
 fixtures/epigraph-role-aria/meta.json         |   10 +
 fixtures/epigraph-role-aria/utterances.json   |    5 +
 fixtures/epilogue-epub-type/gnd.json          |    6 +
 fixtures/epilogue-epub-type/input.html        |   11 +
 fixtures/epilogue-epub-type/meta.json         |   10 +
 fixtures/epilogue-epub-type/utterances.json   |    5 +
 fixtures/epilogue-role-aria/gnd.json          |    6 +
 fixtures/epilogue-role-aria/input.html        |    1 +
 fixtures/epilogue-role-aria/meta.json         |   10 +
 fixtures/epilogue-role-aria/utterances.json   |    5 +
 fixtures/errata-epub-type/gnd.json            |    6 +
 fixtures/errata-epub-type/input.html          |   11 +
 fixtures/errata-epub-type/meta.json           |   10 +
 fixtures/errata-epub-type/utterances.json     |    5 +
 fixtures/errata-role-aria/gnd.json            |    6 +
 fixtures/errata-role-aria/input.html          |    1 +
 fixtures/errata-role-aria/meta.json           |   10 +
 fixtures/errata-role-aria/utterances.json     |    5 +
 fixtures/example-epub-type/gnd.json           |    6 +
 fixtures/example-epub-type/input.html         |   11 +
 fixtures/example-epub-type/meta.json          |   10 +
 fixtures/example-epub-type/utterances.json    |    5 +
 fixtures/example-role-aria/gnd.json           |    6 +
 fixtures/example-role-aria/input.html         |    1 +
 fixtures/example-role-aria/meta.json          |   10 +
 fixtures/example-role-aria/utterances.json    |    5 +
 fixtures/figure-basic-epub-type/gnd.json      |   14 +
 fixtures/figure-basic-epub-type/input.html    |   13 +
 fixtures/figure-basic-epub-type/meta.json     |   10 +
 .../figure-basic-epub-type/utterances.json    |    5 +
 fixtures/figure-basic-html-native/gnd.json    |   14 +
 fixtures/figure-basic-html-native/input.html  |    3 +
 fixtures/figure-basic-html-native/meta.json   |   10 +
 .../figure-basic-html-native/utterances.json  |    5 +
 fixtures/figure-basic-role-aria/gnd.json      |   14 +
 fixtures/figure-basic-role-aria/input.html    |    3 +
 fixtures/figure-basic-role-aria/meta.json     |   10 +
 .../figure-basic-role-aria/utterances.json    |    5 +
 fixtures/figure-caption-html-native/gnd.json  |    6 +
 .../figure-caption-html-native/input.html     |   11 +
 fixtures/figure-caption-html-native/meta.json |   11 +
 .../utterances.json                           |    5 +
 fixtures/figure-caption-role-aria/gnd.json    |    6 +
 fixtures/figure-caption-role-aria/input.html  |   11 +
 fixtures/figure-caption-role-aria/meta.json   |   11 +
 .../figure-caption-role-aria/utterances.json  |    5 +
 fixtures/figure-describedby/gnd.json          |   15 +
 fixtures/figure-describedby/input.html        |    4 +
 fixtures/figure-describedby/meta.json         |   11 +
 fixtures/figure-describedby/utterances.json   |    5 +
 fixtures/footnote-epub-type/gnd.json          |   32 +
 fixtures/footnote-epub-type/input.html        |   12 +
 fixtures/footnote-epub-type/meta.json         |   11 +
 fixtures/footnote-epub-type/utterances.json   |    8 +
 fixtures/footnote-role-aria/gnd.json          |   32 +
 fixtures/footnote-role-aria/input.html        |    2 +
 fixtures/footnote-role-aria/meta.json         |   11 +
 fixtures/footnote-role-aria/utterances.json   |    8 +
 fixtures/glossary-epub-type/gnd.json          |   31 +
 fixtures/glossary-epub-type/input.html        |   16 +
 fixtures/glossary-epub-type/meta.json         |   12 +
 fixtures/glossary-epub-type/utterances.json   |   14 +
 fixtures/glossary-role-aria/gnd.json          |   31 +
 fixtures/glossary-role-aria/input.html        |    6 +
 fixtures/glossary-role-aria/meta.json         |   12 +
 fixtures/glossary-role-aria/utterances.json   |   14 +
 fixtures/glossref-epub-type/gnd.json          |    7 +
 fixtures/glossref-epub-type/input.html        |   11 +
 fixtures/glossref-epub-type/meta.json         |   10 +
 fixtures/glossref-epub-type/utterances.json   |    5 +
 fixtures/glossref-role-aria/gnd.json          |    7 +
 fixtures/glossref-role-aria/input.html        |    1 +
 fixtures/glossref-role-aria/meta.json         |   10 +
 fixtures/glossref-role-aria/utterances.json   |    5 +
 fixtures/header-html-native/gnd.json          |    6 +
 fixtures/header-html-native/input.html        |    1 +
 fixtures/header-html-native/meta.json         |   10 +
 fixtures/header-html-native/utterances.json   |    5 +
 fixtures/heading-html-native/gnd.json         |   40 +
 fixtures/heading-html-native/input.html       |    6 +
 fixtures/heading-html-native/meta.json        |   15 +
 fixtures/heading-html-native/utterances.json  |   20 +
 fixtures/heading-role-aria/gnd.json           |   40 +
 fixtures/heading-role-aria/input.html         |    6 +
 fixtures/heading-role-aria/meta.json          |   15 +
 fixtures/heading-role-aria/utterances.json    |   20 +
 fixtures/image-alt-html-native/gnd.json       |    7 +
 fixtures/image-alt-html-native/input.html     |    1 +
 fixtures/image-alt-html-native/meta.json      |   10 +
 .../image-alt-html-native/utterances.json     |    5 +
 fixtures/image-decorative-empty-alt/gnd.json  |    5 +
 .../image-decorative-empty-alt/input.html     |    1 +
 fixtures/image-decorative-empty-alt/meta.json |   10 +
 .../utterances.json                           |    1 +
 .../gnd.json                                  |    5 +
 .../input.html                                |    1 +
 .../meta.json                                 |   10 +
 .../utterances.json                           |    1 +
 fixtures/image-role-aria/gnd.json             |    6 +
 fixtures/image-role-aria/input.html           |    7 +
 fixtures/image-role-aria/meta.json            |   10 +
 fixtures/image-role-aria/utterances.json      |    5 +
 fixtures/index-epub-type/gnd.json             |   28 +
 fixtures/index-epub-type/input.html           |   16 +
 fixtures/index-epub-type/meta.json            |   12 +
 fixtures/index-epub-type/utterances.json      |    8 +
 fixtures/index-role-aria/gnd.json             |   28 +
 fixtures/index-role-aria/input.html           |    6 +
 fixtures/index-role-aria/meta.json            |   12 +
 fixtures/index-role-aria/utterances.json      |    8 +
 fixtures/introduction-epub-type/gnd.json      |    6 +
 fixtures/introduction-epub-type/input.html    |   11 +
 fixtures/introduction-epub-type/meta.json     |   10 +
 .../introduction-epub-type/utterances.json    |    5 +
 fixtures/introduction-role-aria/gnd.json      |    6 +
 fixtures/introduction-role-aria/input.html    |    1 +
 fixtures/introduction-role-aria/meta.json     |   10 +
 .../introduction-role-aria/utterances.json    |    5 +
 fixtures/landmarks-epub-type/gnd.json         |   35 +
 fixtures/landmarks-epub-type/input.html       |   17 +
 fixtures/landmarks-epub-type/meta.json        |   12 +
 fixtures/landmarks-epub-type/utterances.json  |   11 +
 fixtures/list-html-native/gnd.json            |   25 +
 fixtures/list-html-native/input.html          |    5 +
 fixtures/list-html-native/meta.json           |   11 +
 fixtures/list-html-native/utterances.json     |   11 +
 fixtures/list-role-aria/gnd.json              |   25 +
 fixtures/list-role-aria/input.html            |    5 +
 fixtures/list-role-aria/meta.json             |   11 +
 fixtures/list-role-aria/utterances.json       |   11 +
 fixtures/loa-epub-type/gnd.json               |   28 +
 fixtures/loa-epub-type/input.html             |   16 +
 fixtures/loa-epub-type/meta.json              |   12 +
 fixtures/loa-epub-type/utterances.json        |    8 +
 fixtures/loi-epub-type/gnd.json               |   28 +
 fixtures/loi-epub-type/input.html             |   16 +
 fixtures/loi-epub-type/meta.json              |   12 +
 fixtures/loi-epub-type/utterances.json        |    8 +
 fixtures/lot-epub-type/gnd.json               |   28 +
 fixtures/lot-epub-type/input.html             |   16 +
 fixtures/lot-epub-type/meta.json              |   12 +
 fixtures/lot-epub-type/utterances.json        |    8 +
 fixtures/lov-epub-type/gnd.json               |   28 +
 fixtures/lov-epub-type/input.html             |   16 +
 fixtures/lov-epub-type/meta.json              |   12 +
 fixtures/lov-epub-type/utterances.json        |    8 +
 fixtures/main-html-native/gnd.json            |    6 +
 fixtures/main-html-native/input.html          |    1 +
 fixtures/main-html-native/meta.json           |   10 +
 fixtures/main-html-native/utterances.json     |    5 +
 fixtures/main-role-aria/gnd.json              |    6 +
 fixtures/main-role-aria/input.html            |    1 +
 fixtures/main-role-aria/meta.json             |   10 +
 fixtures/main-role-aria/utterances.json       |    5 +
 fixtures/manifest.json                        | 1333 +++++++++++++++++
 fixtures/math-html-native/gnd.json            |    6 +
 fixtures/math-html-native/input.html          |    7 +
 fixtures/math-html-native/meta.json           |   10 +
 fixtures/math-html-native/utterances.json     |    5 +
 fixtures/math-role-aria/gnd.json              |    6 +
 fixtures/math-role-aria/input.html            |    1 +
 fixtures/math-role-aria/meta.json             |   10 +
 fixtures/math-role-aria/utterances.json       |    5 +
 fixtures/navigation-html-native/gnd.json      |    6 +
 fixtures/navigation-html-native/input.html    |    1 +
 fixtures/navigation-html-native/meta.json     |   10 +
 .../navigation-html-native/utterances.json    |    5 +
 fixtures/navigation-role-aria/gnd.json        |    6 +
 fixtures/navigation-role-aria/input.html      |    1 +
 fixtures/navigation-role-aria/meta.json       |   10 +
 fixtures/navigation-role-aria/utterances.json |    5 +
 fixtures/notice-epub-type/gnd.json            |    6 +
 fixtures/notice-epub-type/input.html          |   11 +
 fixtures/notice-epub-type/meta.json           |   10 +
 fixtures/notice-epub-type/utterances.json     |    5 +
 fixtures/notice-role-aria/gnd.json            |    6 +
 fixtures/notice-role-aria/input.html          |    1 +
 fixtures/notice-role-aria/meta.json           |   10 +
 fixtures/notice-role-aria/utterances.json     |    5 +
 fixtures/pagebreak-epub-type/gnd.json         |   22 +
 fixtures/pagebreak-epub-type/input.html       |   13 +
 fixtures/pagebreak-epub-type/meta.json        |   10 +
 fixtures/pagebreak-epub-type/utterances.json  |   11 +
 fixtures/pagebreak-role-aria/gnd.json         |   22 +
 fixtures/pagebreak-role-aria/input.html       |    3 +
 fixtures/pagebreak-role-aria/meta.json        |   10 +
 fixtures/pagebreak-role-aria/utterances.json  |   11 +
 fixtures/pagelist-epub-type/gnd.json          |   35 +
 fixtures/pagelist-epub-type/input.html        |   17 +
 fixtures/pagelist-epub-type/meta.json         |   12 +
 fixtures/pagelist-epub-type/utterances.json   |   11 +
 fixtures/pagelist-role-aria/gnd.json          |   35 +
 fixtures/pagelist-role-aria/input.html        |    7 +
 fixtures/pagelist-role-aria/meta.json         |   12 +
 fixtures/pagelist-role-aria/utterances.json   |   11 +
 fixtures/paragraph-basic/gnd.json             |    6 +
 fixtures/paragraph-basic/input.html           |    1 +
 fixtures/paragraph-basic/meta.json            |   10 +
 fixtures/paragraph-basic/utterances.json      |    5 +
 .../paragraph-multilingual-ssml-lang/gnd.json |    9 +
 .../input.html                                |    1 +
 .../meta.json                                 |   10 +
 .../utterances.json                           |    7 +
 .../gnd.json                                  |   25 +
 .../input.html                                |    1 +
 .../meta.json                                 |   10 +
 .../utterances.json                           |   14 +
 fixtures/part-epub-type/gnd.json              |   13 +
 fixtures/part-epub-type/input.html            |   13 +
 fixtures/part-epub-type/meta.json             |   11 +
 fixtures/part-epub-type/utterances.json       |    5 +
 fixtures/part-role-aria/gnd.json              |   13 +
 fixtures/part-role-aria/input.html            |    3 +
 fixtures/part-role-aria/meta.json             |   11 +
 fixtures/part-role-aria/utterances.json       |    5 +
 fixtures/preface-epub-type/gnd.json           |    6 +
 fixtures/preface-epub-type/input.html         |   11 +
 fixtures/preface-epub-type/meta.json          |   10 +
 fixtures/preface-epub-type/utterances.json    |    5 +
 fixtures/preface-role-aria/gnd.json           |    6 +
 fixtures/preface-role-aria/input.html         |    1 +
 fixtures/preface-role-aria/meta.json          |   10 +
 fixtures/preface-role-aria/utterances.json    |    5 +
 fixtures/preformatted-html-native/gnd.json    |    6 +
 fixtures/preformatted-html-native/input.html  |    2 +
 fixtures/preformatted-html-native/meta.json   |   10 +
 .../preformatted-html-native/utterances.json  |    5 +
 fixtures/presentation-role-aria/gnd.json      |    6 +
 fixtures/presentation-role-aria/input.html    |    1 +
 fixtures/presentation-role-aria/meta.json     |   10 +
 .../presentation-role-aria/utterances.json    |    5 +
 fixtures/prologue-epub-type/gnd.json          |    6 +
 fixtures/prologue-epub-type/input.html        |   11 +
 fixtures/prologue-epub-type/meta.json         |   10 +
 fixtures/prologue-epub-type/utterances.json   |    5 +
 fixtures/prologue-role-aria/gnd.json          |    6 +
 fixtures/prologue-role-aria/input.html        |    1 +
 fixtures/prologue-role-aria/meta.json         |   10 +
 fixtures/prologue-role-aria/utterances.json   |    5 +
 fixtures/pullquote-epub-type/gnd.json         |    6 +
 fixtures/pullquote-epub-type/input.html       |   11 +
 fixtures/pullquote-epub-type/meta.json        |   10 +
 fixtures/pullquote-epub-type/utterances.json  |    5 +
 fixtures/pullquote-role-aria/gnd.json         |    6 +
 fixtures/pullquote-role-aria/input.html       |    1 +
 fixtures/pullquote-role-aria/meta.json        |   10 +
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 fixtures/qna-epub-type/input.html             |   11 +
 fixtures/qna-epub-type/meta.json              |   10 +
 fixtures/qna-epub-type/utterances.json        |    5 +
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 fixtures/qna-role-aria/input.html             |    1 +
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 fixtures/qna-role-aria/utterances.json        |    5 +
 fixtures/region-role-aria/gnd.json            |    6 +
 fixtures/region-role-aria/input.html          |    1 +
 fixtures/region-role-aria/meta.json           |   10 +
 fixtures/region-role-aria/utterances.json     |    5 +
 fixtures/separator-html-native/gnd.json       |    6 +
 fixtures/separator-html-native/input.html     |    1 +
 fixtures/separator-html-native/meta.json      |   10 +
 .../separator-html-native/utterances.json     |    1 +
 fixtures/separator-role-aria/gnd.json         |    5 +
 fixtures/separator-role-aria/input.html       |    1 +
 fixtures/separator-role-aria/meta.json        |   10 +
 fixtures/separator-role-aria/utterances.json  |    1 +
 fixtures/subtitle-epub-type/gnd.json          |    6 +
 fixtures/subtitle-epub-type/input.html        |   11 +
 fixtures/subtitle-epub-type/meta.json         |   10 +
 fixtures/subtitle-epub-type/utterances.json   |    5 +
 fixtures/subtitle-role-aria/gnd.json          |    6 +
 fixtures/subtitle-role-aria/input.html        |    1 +
 fixtures/subtitle-role-aria/meta.json         |   10 +
 fixtures/subtitle-role-aria/utterances.json   |    5 +
 fixtures/summary-html-native/gnd.json         |    6 +
 fixtures/summary-html-native/input.html       |    1 +
 fixtures/summary-html-native/meta.json        |   10 +
 fixtures/summary-html-native/utterances.json  |    5 +
 fixtures/table-html-native/gnd.json           |   64 +
 fixtures/table-html-native/input.html         |    5 +
 fixtures/table-html-native/meta.json          |   13 +
 fixtures/table-html-native/utterances.json    |   20 +
 fixtures/table-role-aria/gnd.json             |   64 +
 fixtures/table-role-aria/input.html           |    5 +
 fixtures/table-role-aria/meta.json            |   13 +
 fixtures/table-role-aria/utterances.json      |   20 +
 fixtures/term-epub-type/gnd.json              |   13 +
 fixtures/term-epub-type/input.html            |   13 +
 fixtures/term-epub-type/meta.json             |   11 +
 fixtures/term-epub-type/utterances.json       |    5 +
 fixtures/term-html-native/gnd.json            |    6 +
 fixtures/term-html-native/input.html          |    1 +
 fixtures/term-html-native/meta.json           |   10 +
 fixtures/term-html-native/utterances.json     |    5 +
 fixtures/term-role-aria/gnd.json              |    6 +
 fixtures/term-role-aria/input.html            |    1 +
 fixtures/term-role-aria/meta.json             |   10 +
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 fixtures/tip-epub-type/gnd.json               |    6 +
 fixtures/tip-epub-type/input.html             |   11 +
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 fixtures/tip-epub-type/utterances.json        |    5 +
 fixtures/tip-role-aria/gnd.json               |    6 +
 fixtures/tip-role-aria/input.html             |    1 +
 fixtures/tip-role-aria/meta.json              |   10 +
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 fixtures/toc-epub-type/gnd.json               |   35 +
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 fixtures/toc-epub-type/meta.json              |   12 +
 fixtures/toc-epub-type/utterances.json        |   11 +
 fixtures/toc-role-aria/gnd.json               |   35 +
 fixtures/toc-role-aria/input.html             |    7 +
 fixtures/toc-role-aria/meta.json              |   12 +
 fixtures/toc-role-aria/utterances.json        |   11 +
 fixtures/video-html-native/gnd.json           |    7 +
 fixtures/video-html-native/input.html         |    1 +
 fixtures/video-html-native/meta.json          |   10 +
 fixtures/video-html-native/utterances.json    |    5 +
 package-lock.json                             |  299 +++-
 package.json                                  |   12 +-
 scripts/build-fixtures-manifest.js            |   85 ++
 src/gnd/index.ts                              |    1 +
 src/gnd/types.ts                              |   36 +
 test/gnd/fixtures.test.ts                     |   38 +
 test/testUtils.ts                             |   49 +
 497 files changed, 6986 insertions(+), 10 deletions(-)
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 create mode 100644 fixtures/pagebreak-role-aria/input.html
 create mode 100644 fixtures/pagebreak-role-aria/meta.json
 create mode 100644 fixtures/pagebreak-role-aria/utterances.json
 create mode 100644 fixtures/pagelist-epub-type/gnd.json
 create mode 100644 fixtures/pagelist-epub-type/input.html
 create mode 100644 fixtures/pagelist-epub-type/meta.json
 create mode 100644 fixtures/pagelist-epub-type/utterances.json
 create mode 100644 fixtures/pagelist-role-aria/gnd.json
 create mode 100644 fixtures/pagelist-role-aria/input.html
 create mode 100644 fixtures/pagelist-role-aria/meta.json
 create mode 100644 fixtures/pagelist-role-aria/utterances.json
 create mode 100644 fixtures/paragraph-basic/gnd.json
 create mode 100644 fixtures/paragraph-basic/input.html
 create mode 100644 fixtures/paragraph-basic/meta.json
 create mode 100644 fixtures/paragraph-basic/utterances.json
 create mode 100644 fixtures/paragraph-multilingual-ssml-lang/gnd.json
 create mode 100644 fixtures/paragraph-multilingual-ssml-lang/input.html
 create mode 100644 fixtures/paragraph-multilingual-ssml-lang/meta.json
 create mode 100644 fixtures/paragraph-multilingual-ssml-lang/utterances.json
 create mode 100644 fixtures/paragraph-multilingual-text-children/gnd.json
 create mode 100644 fixtures/paragraph-multilingual-text-children/input.html
 create mode 100644 fixtures/paragraph-multilingual-text-children/meta.json
 create mode 100644 fixtures/paragraph-multilingual-text-children/utterances.json
 create mode 100644 fixtures/part-epub-type/gnd.json
 create mode 100644 fixtures/part-epub-type/input.html
 create mode 100644 fixtures/part-epub-type/meta.json
 create mode 100644 fixtures/part-epub-type/utterances.json
 create mode 100644 fixtures/part-role-aria/gnd.json
 create mode 100644 fixtures/part-role-aria/input.html
 create mode 100644 fixtures/part-role-aria/meta.json
 create mode 100644 fixtures/part-role-aria/utterances.json
 create mode 100644 fixtures/preface-epub-type/gnd.json
 create mode 100644 fixtures/preface-epub-type/input.html
 create mode 100644 fixtures/preface-epub-type/meta.json
 create mode 100644 fixtures/preface-epub-type/utterances.json
 create mode 100644 fixtures/preface-role-aria/gnd.json
 create mode 100644 fixtures/preface-role-aria/input.html
 create mode 100644 fixtures/preface-role-aria/meta.json
 create mode 100644 fixtures/preface-role-aria/utterances.json
 create mode 100644 fixtures/preformatted-html-native/gnd.json
 create mode 100644 fixtures/preformatted-html-native/input.html
 create mode 100644 fixtures/preformatted-html-native/meta.json
 create mode 100644 fixtures/preformatted-html-native/utterances.json
 create mode 100644 fixtures/presentation-role-aria/gnd.json
 create mode 100644 fixtures/presentation-role-aria/input.html
 create mode 100644 fixtures/presentation-role-aria/meta.json
 create mode 100644 fixtures/presentation-role-aria/utterances.json
 create mode 100644 fixtures/prologue-epub-type/gnd.json
 create mode 100644 fixtures/prologue-epub-type/input.html
 create mode 100644 fixtures/prologue-epub-type/meta.json
 create mode 100644 fixtures/prologue-epub-type/utterances.json
 create mode 100644 fixtures/prologue-role-aria/gnd.json
 create mode 100644 fixtures/prologue-role-aria/input.html
 create mode 100644 fixtures/prologue-role-aria/meta.json
 create mode 100644 fixtures/prologue-role-aria/utterances.json
 create mode 100644 fixtures/pullquote-epub-type/gnd.json
 create mode 100644 fixtures/pullquote-epub-type/input.html
 create mode 100644 fixtures/pullquote-epub-type/meta.json
 create mode 100644 fixtures/pullquote-epub-type/utterances.json
 create mode 100644 fixtures/pullquote-role-aria/gnd.json
 create mode 100644 fixtures/pullquote-role-aria/input.html
 create mode 100644 fixtures/pullquote-role-aria/meta.json
 create mode 100644 fixtures/pullquote-role-aria/utterances.json
 create mode 100644 fixtures/qna-epub-type/gnd.json
 create mode 100644 fixtures/qna-epub-type/input.html
 create mode 100644 fixtures/qna-epub-type/meta.json
 create mode 100644 fixtures/qna-epub-type/utterances.json
 create mode 100644 fixtures/qna-role-aria/gnd.json
 create mode 100644 fixtures/qna-role-aria/input.html
 create mode 100644 fixtures/qna-role-aria/meta.json
 create mode 100644 fixtures/qna-role-aria/utterances.json
 create mode 100644 fixtures/region-role-aria/gnd.json
 create mode 100644 fixtures/region-role-aria/input.html
 create mode 100644 fixtures/region-role-aria/meta.json
 create mode 100644 fixtures/region-role-aria/utterances.json
 create mode 100644 fixtures/separator-html-native/gnd.json
 create mode 100644 fixtures/separator-html-native/input.html
 create mode 100644 fixtures/separator-html-native/meta.json
 create mode 100644 fixtures/separator-html-native/utterances.json
 create mode 100644 fixtures/separator-role-aria/gnd.json
 create mode 100644 fixtures/separator-role-aria/input.html
 create mode 100644 fixtures/separator-role-aria/meta.json
 create mode 100644 fixtures/separator-role-aria/utterances.json
 create mode 100644 fixtures/subtitle-epub-type/gnd.json
 create mode 100644 fixtures/subtitle-epub-type/input.html
 create mode 100644 fixtures/subtitle-epub-type/meta.json
 create mode 100644 fixtures/subtitle-epub-type/utterances.json
 create mode 100644 fixtures/subtitle-role-aria/gnd.json
 create mode 100644 fixtures/subtitle-role-aria/input.html
 create mode 100644 fixtures/subtitle-role-aria/meta.json
 create mode 100644 fixtures/subtitle-role-aria/utterances.json
 create mode 100644 fixtures/summary-html-native/gnd.json
 create mode 100644 fixtures/summary-html-native/input.html
 create mode 100644 fixtures/summary-html-native/meta.json
 create mode 100644 fixtures/summary-html-native/utterances.json
 create mode 100644 fixtures/table-html-native/gnd.json
 create mode 100644 fixtures/table-html-native/input.html
 create mode 100644 fixtures/table-html-native/meta.json
 create mode 100644 fixtures/table-html-native/utterances.json
 create mode 100644 fixtures/table-role-aria/gnd.json
 create mode 100644 fixtures/table-role-aria/input.html
 create mode 100644 fixtures/table-role-aria/meta.json
 create mode 100644 fixtures/table-role-aria/utterances.json
 create mode 100644 fixtures/term-epub-type/gnd.json
 create mode 100644 fixtures/term-epub-type/input.html
 create mode 100644 fixtures/term-epub-type/meta.json
 create mode 100644 fixtures/term-epub-type/utterances.json
 create mode 100644 fixtures/term-html-native/gnd.json
 create mode 100644 fixtures/term-html-native/input.html
 create mode 100644 fixtures/term-html-native/meta.json
 create mode 100644 fixtures/term-html-native/utterances.json
 create mode 100644 fixtures/term-role-aria/gnd.json
 create mode 100644 fixtures/term-role-aria/input.html
 create mode 100644 fixtures/term-role-aria/meta.json
 create mode 100644 fixtures/term-role-aria/utterances.json
 create mode 100644 fixtures/tip-epub-type/gnd.json
 create mode 100644 fixtures/tip-epub-type/input.html
 create mode 100644 fixtures/tip-epub-type/meta.json
 create mode 100644 fixtures/tip-epub-type/utterances.json
 create mode 100644 fixtures/tip-role-aria/gnd.json
 create mode 100644 fixtures/tip-role-aria/input.html
 create mode 100644 fixtures/tip-role-aria/meta.json
 create mode 100644 fixtures/tip-role-aria/utterances.json
 create mode 100644 fixtures/toc-epub-type/gnd.json
 create mode 100644 fixtures/toc-epub-type/input.html
 create mode 100644 fixtures/toc-epub-type/meta.json
 create mode 100644 fixtures/toc-epub-type/utterances.json
 create mode 100644 fixtures/toc-role-aria/gnd.json
 create mode 100644 fixtures/toc-role-aria/input.html
 create mode 100644 fixtures/toc-role-aria/meta.json
 create mode 100644 fixtures/toc-role-aria/utterances.json
 create mode 100644 fixtures/video-html-native/gnd.json
 create mode 100644 fixtures/video-html-native/input.html
 create mode 100644 fixtures/video-html-native/meta.json
 create mode 100644 fixtures/video-html-native/utterances.json
 create mode 100644 scripts/build-fixtures-manifest.js
 create mode 100644 src/gnd/index.ts
 create mode 100644 src/gnd/types.ts
 create mode 100644 test/gnd/fixtures.test.ts

diff --git a/demo/playground/index.html b/demo/playground/index.html
new file mode 100644
index 0000000..3a83216
--- /dev/null
+++ b/demo/playground/index.html
@@ -0,0 +1,63 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+  <meta charset="UTF-8">
+  <meta name="viewport" content="width=device-width, initial-scale=1.0">
+  <title>Guided Navigation Fixture Playground</title>
+  <link rel="stylesheet" href="./styles.css">
+</head>
+<body>
+  <aside class="sidebar">
+    <div class="sidebar-header">
+      <h1>Fixtures</h1>
+      <input type="search" id="filter-input" placeholder="Filter (e.g. footnote, epub-type)">
+    </div>
+    <div id="fixture-list" class="fixture-list"></div>
+  </aside>
+
+  <main class="content">
+    <div id="fixture-meta" class="fixture-meta"></div>
+
+    <div class="pane">
+      <h2>1. Input HTML</h2>
+      <pre id="input-html" class="code-block"></pre>
+    </div>
+
+    <div class="pane">
+      <div class="pane-header">
+        <h2>2. Guided Navigation document</h2>
+        <span id="gnd-badge" class="badge"></span>
+      </div>
+      <div class="compare-grid">
+        <div>
+          <h3>Expected</h3>
+          <pre id="gnd-expected" class="code-block"></pre>
+        </div>
+        <div>
+          <h3>Actual</h3>
+          <pre id="gnd-actual" class="code-block"></pre>
+        </div>
+      </div>
+    </div>
+
+    <div class="pane">
+      <div class="pane-header">
+        <h2>3. Utterances</h2>
+        <span id="utterances-badge" class="badge"></span>
+      </div>
+      <div class="compare-grid">
+        <div>
+          <h3>Expected</h3>
+          <pre id="utterances-expected" class="code-block"></pre>
+        </div>
+        <div>
+          <h3>Actual</h3>
+          <pre id="utterances-actual" class="code-block"></pre>
+        </div>
+      </div>
+    </div>
+  </main>
+
+  <script type="module" src="./script.js"></script>
+</body>
+</html>
diff --git a/demo/playground/script.js b/demo/playground/script.js
new file mode 100644
index 0000000..0cab911
--- /dev/null
+++ b/demo/playground/script.js
@@ -0,0 +1,166 @@
+const filterInput = document.getElementById("filter-input");
+const fixtureListEl = document.getElementById("fixture-list");
+const fixtureMetaEl = document.getElementById("fixture-meta");
+const inputHtmlEl = document.getElementById("input-html");
+const gndExpectedEl = document.getElementById("gnd-expected");
+const gndActualEl = document.getElementById("gnd-actual");
+const gndBadgeEl = document.getElementById("gnd-badge");
+const utterancesExpectedEl = document.getElementById("utterances-expected");
+const utterancesActualEl = document.getElementById("utterances-actual");
+const utterancesBadgeEl = document.getElementById("utterances-badge");
+
+// Feature-detect a real pipeline, if/when @readium/speech exports one. Until
+// then, every "actual" pane just shows a "not implemented yet" badge.
+let pipeline = null;
+try {
+  const mod = await import("../../build/index.js");
+  if (typeof mod.htmlToGnd === "function" && typeof mod.gndToUtterances === "function") {
+    pipeline = mod;
+  }
+} catch {
+  // build/index.js may not export a pipeline yet; that's expected pre-implementation.
+}
+
+const manifest = await fetch("../../fixtures/manifest.json").then((r) => r.json());
+manifest.sort((a, b) => a.role.localeCompare(b.role) || a.description.localeCompare(b.description));
+
+let selectedId = null;
+
+// Matches against what's actually shown to the user (role, description) —
+// not the roles.md-internal "tier"/"pathway" bookkeeping, which isn't (and
+// shouldn't be) displayed as a navigable concept anywhere in this UI.
+function matchesFilter(fixture, filter) {
+  return [fixture.role, fixture.description].join(" ").toLowerCase().includes(filter);
+}
+
+function renderList() {
+  const filter = filterInput.value.trim().toLowerCase();
+  const filtering = filter.length > 0;
+  const filtered = filtering ? manifest.filter((f) => matchesFilter(f, filter)) : manifest;
+
+  fixtureListEl.innerHTML = "";
+
+  if (filtered.length === 0) {
+    const empty = document.createElement("div");
+    empty.className = "no-results";
+    empty.textContent = "No fixtures match.";
+    fixtureListEl.appendChild(empty);
+    return;
+  }
+
+  const byRole = new Map();
+  for (const fixture of filtered) {
+    if (!byRole.has(fixture.role)) byRole.set(fixture.role, []);
+    byRole.get(fixture.role).push(fixture);
+  }
+
+  let firstGroup = true;
+  for (const [role, fixtures] of byRole) {
+    const details = document.createElement("details");
+    details.className = "role-group";
+    // While filtering, force every matching group open so results are never
+    // hidden inside a collapsed section. Otherwise, only the first group
+    // (or the one containing the currently selected fixture) starts open.
+    details.open = filtering || firstGroup || fixtures.some((f) => f.id === selectedId);
+    firstGroup = false;
+
+    const summary = document.createElement("summary");
+    summary.textContent = role;
+    details.appendChild(summary);
+
+    const ul = document.createElement("ul");
+    for (const fixture of fixtures) {
+      const li = document.createElement("li");
+      li.dataset.id = fixture.id;
+      li.className = fixture.id === selectedId ? "active" : "";
+      li.textContent = fixture.description;
+      li.addEventListener("click", () => selectFixture(fixture.id));
+      ul.appendChild(li);
+    }
+    details.appendChild(ul);
+    fixtureListEl.appendChild(details);
+  }
+
+  if (!selectedId && filtered.length > 0) selectFixture(filtered[0].id);
+}
+
+function deepEqual(a, b) {
+  return JSON.stringify(sortKeysDeep(a)) === JSON.stringify(sortKeysDeep(b));
+}
+
+function sortKeysDeep(value) {
+  if (Array.isArray(value)) return value.map(sortKeysDeep);
+  if (value && typeof value === "object") {
+    return Object.keys(value)
+      .sort()
+      .reduce((acc, key) => {
+        acc[key] = sortKeysDeep(value[key]);
+        return acc;
+      }, {});
+  }
+  return value;
+}
+
+function setBadge(el, state) {
+  el.textContent = state === "pass" ? "pass" : state === "fail" ? "fail" : "not implemented yet";
+  el.className = `badge ${state}`;
+}
+
+async function selectFixture(id) {
+  selectedId = id;
+  for (const li of fixtureListEl.querySelectorAll("li[data-id]")) {
+    li.classList.toggle("active", li.dataset.id === id);
+  }
+
+  const entry = manifest.find((f) => f.id === id);
+  const base = `../../fixtures/${entry.dir}/`;
+
+  const [meta, inputHtml, gnd, utterances] = await Promise.all([
+    fetch(base + "meta.json").then((r) => r.json()),
+    fetch(base + entry.files.input).then((r) => r.text()),
+    fetch(base + entry.files.gnd).then((r) => r.json()),
+    fetch(base + entry.files.utterances).then((r) => r.json()),
+  ]);
+
+  fixtureMetaEl.replaceChildren();
+
+  const heading = document.createElement("h2");
+  heading.textContent = meta.description;
+  fixtureMetaEl.appendChild(heading);
+
+  const idLine = document.createElement("p");
+  idLine.className = "fixture-id";
+  idLine.textContent = meta.id;
+  fixtureMetaEl.appendChild(idLine);
+
+  inputHtmlEl.textContent = inputHtml;
+  gndExpectedEl.textContent = JSON.stringify(gnd, null, 2);
+  utterancesExpectedEl.textContent = JSON.stringify(utterances, null, 2);
+
+  if (!pipeline) {
+    gndActualEl.textContent = "";
+    utterancesActualEl.textContent = "";
+    setBadge(gndBadgeEl, "pending");
+    setBadge(utterancesBadgeEl, "pending");
+    return;
+  }
+
+  try {
+    const actualGnd = pipeline.htmlToGnd(inputHtml, { inputKind: meta.inputKind });
+    gndActualEl.textContent = JSON.stringify(actualGnd, null, 2);
+    setBadge(gndBadgeEl, deepEqual(actualGnd, gnd) ? "pass" : "fail");
+
+    const actualUtterances = pipeline.gndToUtterances(actualGnd);
+    utterancesActualEl.textContent = JSON.stringify(actualUtterances, null, 2);
+    setBadge(utterancesBadgeEl, deepEqual(actualUtterances, utterances) ? "pass" : "fail");
+  } catch (err) {
+    gndActualEl.textContent = String(err);
+    utterancesActualEl.textContent = "";
+    setBadge(gndBadgeEl, "fail");
+    setBadge(utterancesBadgeEl, "fail");
+  }
+}
+
+filterInput.addEventListener("input", renderList);
+
+renderList();
diff --git a/demo/playground/styles.css b/demo/playground/styles.css
new file mode 100644
index 0000000..981e426
--- /dev/null
+++ b/demo/playground/styles.css
@@ -0,0 +1,226 @@
+* {
+  box-sizing: border-box;
+}
+
+html, body {
+  margin: 0;
+  padding: 0;
+  height: 100%;
+  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
+  color: #333;
+}
+
+body {
+  display: flex;
+  align-items: stretch;
+}
+
+/* ---- Sidebar: every fixture, one flat scrollable list, no gating step ---- */
+
+.sidebar {
+  width: 320px;
+  flex-shrink: 0;
+  height: 100vh;
+  overflow-y: auto;
+  border-right: 1px solid #ddd;
+  background: #f7f7f8;
+  display: flex;
+  flex-direction: column;
+}
+
+.sidebar-header {
+  position: sticky;
+  top: 0;
+  background: #f7f7f8;
+  padding: 14px 14px 10px;
+  border-bottom: 1px solid #ddd;
+}
+
+.sidebar-header h1 {
+  font-size: 1.1em;
+  margin: 0 0 8px 0;
+}
+
+#filter-input {
+  width: 100%;
+  padding: 6px 8px;
+  border: 1px solid #767676;
+  border-radius: 5px;
+  font-size: 0.9em;
+  color: #333;
+  background: #fff;
+}
+
+.fixture-list {
+  padding: 6px 0;
+  flex: 1;
+}
+
+.fixture-list .role-group {
+  border-bottom: 1px solid #eaeaea;
+}
+
+.fixture-list .role-group summary {
+  cursor: pointer;
+  padding: 8px 14px;
+  font-size: 0.9em;
+  font-weight: 700;
+  color: #333;
+  list-style: none;
+  user-select: none;
+}
+
+.fixture-list .role-group summary::-webkit-details-marker {
+  display: none;
+}
+
+.fixture-list .role-group summary::before {
+  content: "▸";
+  display: inline-block;
+  width: 1em;
+  color: #555;
+}
+
+.fixture-list .role-group[open] summary::before {
+  content: "▾";
+}
+
+.fixture-list .role-group summary:hover {
+  background: #ececee;
+}
+
+.fixture-list .role-group ul {
+  list-style: none;
+  margin: 0;
+  padding: 0 0 4px;
+}
+
+.fixture-list li {
+  padding: 6px 14px 6px 26px;
+  cursor: pointer;
+  font-size: 0.88em;
+  line-height: 1.3;
+  border-left: 3px solid transparent;
+}
+
+.fixture-list li:hover {
+  background: #ececee;
+}
+
+.fixture-list li.active {
+  background: #e4e9fd;
+  border-left-color: #3a5cf5;
+  font-weight: 600;
+}
+
+.fixture-list .no-results {
+  padding: 10px 14px;
+  color: #5a5a5a;
+  font-size: 0.88em;
+}
+
+/* ---- Main content ---- */
+
+.content {
+  flex: 1;
+  height: 100vh;
+  overflow-y: auto;
+  padding: 20px 28px;
+}
+
+.fixture-meta {
+  margin-bottom: 20px;
+  font-size: 0.95em;
+  color: #444;
+}
+
+.fixture-meta h2 {
+  margin: 0 0 4px 0;
+}
+
+.fixture-meta .fixture-id {
+  font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
+  font-size: 0.8em;
+  color: #666;
+  margin: 8px 0 0 0;
+}
+
+.pane {
+  margin-bottom: 24px;
+}
+
+.pane h2 {
+  font-size: 1.05em;
+}
+
+.pane-header {
+  display: flex;
+  align-items: center;
+  gap: 10px;
+}
+
+.pane-header h2 {
+  margin: 0;
+}
+
+.compare-grid {
+  display: grid;
+  grid-template-columns: 1fr 1fr;
+  gap: 16px;
+}
+
+.compare-grid h3 {
+  margin: 0 0 6px 0;
+  font-size: 0.9em;
+  color: #666;
+}
+
+.code-block {
+  background: #fff;
+  border: 1px solid #ddd;
+  border-radius: 6px;
+  padding: 10px;
+  overflow-x: auto;
+  white-space: pre-wrap;
+  word-break: break-word;
+  font-size: 0.85em;
+}
+
+.badge {
+  display: inline-block;
+  padding: 2px 8px;
+  border-radius: 10px;
+  font-size: 0.8em;
+  font-weight: 600;
+}
+
+.badge.pass {
+  background: #d4edda;
+  color: #155724;
+}
+
+.badge.fail {
+  background: #f8d7da;
+  color: #721c24;
+}
+
+.badge.pending {
+  background: #e2e3e5;
+  color: #383d41;
+}
+
+@media (max-width: 800px) {
+  body {
+    flex-direction: column;
+  }
+  .sidebar {
+    width: 100%;
+    height: 40vh;
+  }
+  .content {
+    height: 60vh;
+  }
+  .compare-grid {
+    grid-template-columns: 1fr;
+  }
+}
diff --git a/fixtures/README.md b/fixtures/README.md
new file mode 100644
index 0000000..2ae831e
--- /dev/null
+++ b/fixtures/README.md
@@ -0,0 +1,165 @@
+# Guided Navigation / Read-Aloud Test Fixtures
+
+This directory is a language-agnostic conformance test suite for three pipeline
+stages used to implement read-aloud/TTS on top of HTML content:
+
+1. **HTML parsing** — reading a document or fragment of HTML/XHTML.
+2. **Guided Navigation (GND) document generation** — mapping the parsed HTML
+   onto the [Guided Navigation](https://github.com/readium/guided-navigation)
+   role vocabulary defined in
+   [`roles.md`](https://github.com/readium/guided-navigation/blob/main/roles.md).
+3. **Utterance extraction** — turning a GND document into an ordered list of
+   read-aloud utterances, following the patterns documented in the
+   [read-aloud examples](https://github.com/readium/guided-navigation/tree/main/examples/read-aloud).
+
+Fixtures here are **plain files on disk** (HTML + JSON) — not code. Any
+platform (TypeScript, Kotlin, Swift, ...) can consume them with nothing more
+than a JSON parser and a file reader. There is no query language, template
+system, or fixture-specific code to learn.
+
+## Directory layout
+
+```
+fixtures/
+  README.md              this file
+  manifest.json          flat index of every fixture, for discovery without a filesystem walk (generated — do not hand-edit)
+  ROLES_COVERAGE.md       flat list of every role covered and its fixtures (generated — do not hand-edit)
+  <fixture-id>/
+    meta.json             fixture metadata
+    input.html             the HTML input (a fragment or a full document, see meta.json.inputKind)
+    gnd.json               the expected Guided Navigation document produced from input.html
+    utterances.json        the expected ordered utterance list produced from gnd.json
+```
+
+`manifest.json` and `ROLES_COVERAGE.md` are both generated from the
+`meta.json` files on disk by `scripts/build-fixtures-manifest.js`
+(`npm run generate-fixtures-manifest`) — the filesystem is the source of
+truth, not either of these files. Never hand-edit them; run the script
+instead.
+
+[roles.md](https://github.com/readium/guided-navigation/blob/main/roles.md)
+was the seed used to originally populate this suite — it is not something
+this suite continues to track itself against. Its tier/table categorization
+does not appear anywhere in `meta.json`, `manifest.json`, or
+`ROLES_COVERAGE.md` — only `role` does, since that's the actual content type
+being tested (a "footnote", a "list", ...), not a classification scheme.
+
+Each fixture directory is fully self-contained and independently loadable.
+
+## Fixture granularity
+
+**One fixture = one distinct, scoped behavior.** Concretely:
+
+- **One fixture per role, per distinct HTML encoding.** roles.md documents
+  up to three ways of expressing a role: a native HTML element, an explicit
+  ARIA role (`role="doc-..."` or a plain ARIA role), and an EPUB `epub:type`
+  attribute. Every one of these is a separate code path through stage 1
+  (HTML parsing), even when two encodings produce an identical GND result —
+  so each gets its own fixture, distinguished by its id/description and
+  visible directly in its `input.html` (e.g. `list-html-native` vs.
+  `list-role-aria` vs. `list-epub-type`). This isn't tracked as a field in
+  `meta.json` — it's not information a consumer needs to look up, just a
+  reason more than one fixture exists for the same role.
+- **Trivial repetition is bundled into one fixture.** `heading1`...`heading6`
+  are the same pathway repeated at six depths, not six distinct behaviors —
+  they live together in one `heading-*` fixture. Multiple `<li>` inside one
+  `<ul>` is one `list-*` fixture, not one per item.
+
+## `meta.json` schema
+
+```jsonc
+{
+  "id": "footnote-epub-type",             // must match the directory name
+  "description": "Footnote encoded via epub:type, referenced by a noteref",
+  "role": "footnote",                     // the roles.md role name this fixture targets
+  "rolesCovered": ["footnote", "noteref"],// every role name this fixture's markup exercises
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "document"                 // "fragment" | "document"
+}
+```
+
+## `epub:type` fixtures are full XHTML documents
+
+`epub:type` is only meaningful in XHTML with the `epub` namespace declared on
+the document root — it is **not** a plain-HTML attribute, and there is no
+"parse it as a literal attribute name in an HTML5 document" fallback: real
+EPUB reading systems parse content documents as namespace-aware XHTML. Every
+`*-epub-type` fixture therefore has `inputKind: "document"` and its
+`input.html` is a complete document:
+
+```xml
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops">
+<head><meta charset="utf-8"/><title>Fixture</title></head>
+<body>
+  <div epub:type="chapter">...</div>
+</body>
+</html>
+```
+
+By contrast, `role-aria` and `html-native` fixtures stay as bare fragments
+(`inputKind: "fragment"`) since ARIA roles and native HTML elements don't
+require any namespace declaration.
+
+## Navigational-list roles
+
+Roles whose roles.md definition is "a list of links to X" or "a collection
+of X" (`landmarks`, `loa`, `loi`, `lot`, `lov`, `pagelist`, `toc`, `index`,
+`bibliography`, `glossary`, `endnotes`, `credits`) are modeled as an actual
+`list`/`listItem` structure, not a flat text blob — because that's what they
+are. A `listItem` that links to a target elsewhere in the work carries a
+`textref` alongside its visible `text`, reusing the same field the
+footnote/endnote fixtures already use for cross-references:
+
+```jsonc
+{ "role": ["listItem"], "text": "Cover", "textref": "cover.xhtml" }
+```
+
+## `manifest.json`
+
+A flat JSON array, one entry per fixture:
+
+```jsonc
+[
+  {
+    "id": "footnote-epub-type",
+    "dir": "footnote-epub-type",
+    "role": "footnote",
+    "description": "Footnote encoded via epub:type, referenced by a noteref",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  }
+]
+```
+
+Any test runner, in any language, reads this one file to discover every
+fixture and resolve its file paths — no directory listing required.
+
+## Consuming a fixture (any platform)
+
+1. Read `manifest.json`, iterate its entries.
+2. For each entry, read `input.html` and run it through your implementation
+   of stage 1 (HTML → GND) — compare the result to `gnd.json`.
+3. Run the resulting GND document through your implementation of stage 2
+   (GND → utterances) — compare the result to `utterances.json`.
+4. A fixture "passes" when both comparisons match exactly.
+
+## Adding a new fixture
+
+1. `mkdir fixtures/<id>` and hand-write `input.html` for the specific
+   markup being tested.
+2. Hand-author `gnd.json` and `utterances.json` — there is no generator for
+   these; they are the ground truth implementations must match.
+3. Write `meta.json`.
+4. Run `npm run generate-fixtures-manifest` to regenerate `manifest.json`
+   and `ROLES_COVERAGE.md` from what's now on disk.
+
+## This suite is not finished
+
+New roles, new encodings, and new real-world edge cases get added to
+`fixtures/` as they're encountered — this is a living suite, not a fixed
+checklist against any external document.
diff --git a/fixtures/ROLES_COVERAGE.md b/fixtures/ROLES_COVERAGE.md
new file mode 100644
index 0000000..68172b1
--- /dev/null
+++ b/fixtures/ROLES_COVERAGE.md
@@ -0,0 +1,76 @@
+# Fixture Coverage
+
+Every role currently covered by a fixture in this directory, generated from
+`fixtures/*/meta.json` by `scripts/build-fixtures-manifest.js` — do not
+hand-edit this file. Run `npm run generate-fixtures-manifest` after adding,
+renaming, or removing a fixture.
+
+| Role | Fixtures |
+| --- | --- |
+| `abstract` | `abstract-epub-type`, `abstract-role-aria` |
+| `acknowledgments` | `acknowledgments-epub-type`, `acknowledgments-role-aria` |
+| `afterword` | `afterword-epub-type`, `afterword-role-aria` |
+| `appendix` | `appendix-epub-type`, `appendix-role-aria` |
+| `article` | `article-html-native` |
+| `aside` | `aside-html-native` |
+| `audio` | `audio-html-native` |
+| `backlink` | `backlink-epub-type`, `backlink-role-aria` |
+| `bibliography` | `bibliography-epub-type`, `bibliography-role-aria` |
+| `biblioref` | `biblioref-epub-type`, `biblioref-role-aria` |
+| `blockquote` | `blockquote-html-native` |
+| `body` | `body-html-native` |
+| `chapter` | `chapter-epub-type`, `chapter-role-aria` |
+| `colophon` | `colophon-epub-type`, `colophon-role-aria` |
+| `complementary` | `complementary-role-aria` |
+| `conclusion` | `conclusion-epub-type`, `conclusion-role-aria` |
+| `cover` | `cover-epub-type`, `cover-role-aria` |
+| `credit` | `credit-epub-type`, `credit-role-aria` |
+| `credits` | `credits-epub-type`, `credits-role-aria` |
+| `dedication` | `dedication-epub-type`, `dedication-role-aria` |
+| `definition` | `definition-epub-type`, `definition-html-native`, `definition-role-aria` |
+| `details` | `details-html-native` |
+| `endnotes` | `endnotes-epub-type`, `endnotes-role-aria` |
+| `epigraph` | `epigraph-epub-type`, `epigraph-role-aria` |
+| `epilogue` | `epilogue-epub-type`, `epilogue-role-aria` |
+| `errata` | `errata-epub-type`, `errata-role-aria` |
+| `example` | `example-epub-type`, `example-role-aria` |
+| `figure` | `figure-basic-epub-type`, `figure-basic-html-native`, `figure-basic-role-aria`, `figure-caption-html-native`, `figure-caption-role-aria`, `figure-describedby` |
+| `footnote` | `footnote-epub-type`, `footnote-role-aria` |
+| `glossary` | `glossary-epub-type`, `glossary-role-aria` |
+| `glossref` | `glossref-epub-type`, `glossref-role-aria` |
+| `header` | `header-html-native` |
+| `heading` | `heading-html-native`, `heading-role-aria` |
+| `image` | `image-alt-html-native`, `image-role-aria` |
+| `index` | `index-epub-type`, `index-role-aria` |
+| `introduction` | `introduction-epub-type`, `introduction-role-aria` |
+| `landmarks` | `landmarks-epub-type` |
+| `list` | `list-html-native`, `list-role-aria` |
+| `loa` | `loa-epub-type` |
+| `loi` | `loi-epub-type` |
+| `lot` | `lot-epub-type` |
+| `lov` | `lov-epub-type` |
+| `main` | `main-html-native`, `main-role-aria` |
+| `math` | `math-html-native`, `math-role-aria` |
+| `navigation` | `navigation-html-native`, `navigation-role-aria` |
+| `notice` | `notice-epub-type`, `notice-role-aria` |
+| `pagebreak` | `pagebreak-epub-type`, `pagebreak-role-aria` |
+| `pagelist` | `pagelist-epub-type`, `pagelist-role-aria` |
+| `paragraph` | `paragraph-basic`, `paragraph-multilingual-ssml-lang`, `paragraph-multilingual-text-children` |
+| `part` | `part-epub-type`, `part-role-aria` |
+| `preface` | `preface-epub-type`, `preface-role-aria` |
+| `preformatted` | `preformatted-html-native` |
+| `presentation` | `image-decorative-empty-alt`, `image-decorative-role-presentation`, `presentation-role-aria` |
+| `prologue` | `prologue-epub-type`, `prologue-role-aria` |
+| `pullquote` | `pullquote-epub-type`, `pullquote-role-aria` |
+| `qna` | `qna-epub-type`, `qna-role-aria` |
+| `region` | `region-role-aria` |
+| `separator` | `separator-html-native`, `separator-role-aria` |
+| `subtitle` | `subtitle-epub-type`, `subtitle-role-aria` |
+| `summary` | `summary-html-native` |
+| `table` | `table-html-native`, `table-role-aria` |
+| `term` | `term-epub-type`, `term-html-native`, `term-role-aria` |
+| `tip` | `tip-epub-type`, `tip-role-aria` |
+| `toc` | `toc-epub-type`, `toc-role-aria` |
+| `video` | `video-html-native` |
+
+121 fixtures across 65 roles.
diff --git a/fixtures/abstract-epub-type/gnd.json b/fixtures/abstract-epub-type/gnd.json
new file mode 100644
index 0000000..feb99f1
--- /dev/null
+++ b/fixtures/abstract-epub-type/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "abstract"
+  ],
+  "text": "This work examines the maintenance of coastal lighthouses in the 19th century."
+}
diff --git a/fixtures/abstract-epub-type/input.html b/fixtures/abstract-epub-type/input.html
new file mode 100644
index 0000000..7eacaac
--- /dev/null
+++ b/fixtures/abstract-epub-type/input.html
@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops">
+<head>
+<meta charset="utf-8"/>
+<title>Fixture</title>
+</head>
+<body>
+<div epub:type="abstract">This work examines the maintenance of coastal lighthouses in the 19th century.</div>
+</body>
+</html>
diff --git a/fixtures/abstract-epub-type/meta.json b/fixtures/abstract-epub-type/meta.json
new file mode 100644
index 0000000..14a6a2b
--- /dev/null
+++ b/fixtures/abstract-epub-type/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "abstract-epub-type",
+  "description": "abstract role via epub:type=\"abstract\"",
+  "role": "abstract",
+  "rolesCovered": [
+    "abstract"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "document"
+}
diff --git a/fixtures/abstract-epub-type/utterances.json b/fixtures/abstract-epub-type/utterances.json
new file mode 100644
index 0000000..015e7d5
--- /dev/null
+++ b/fixtures/abstract-epub-type/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "This work examines the maintenance of coastal lighthouses in the 19th century."
+  }
+]
diff --git a/fixtures/abstract-role-aria/gnd.json b/fixtures/abstract-role-aria/gnd.json
new file mode 100644
index 0000000..feb99f1
--- /dev/null
+++ b/fixtures/abstract-role-aria/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "abstract"
+  ],
+  "text": "This work examines the maintenance of coastal lighthouses in the 19th century."
+}
diff --git a/fixtures/abstract-role-aria/input.html b/fixtures/abstract-role-aria/input.html
new file mode 100644
index 0000000..ea23842
--- /dev/null
+++ b/fixtures/abstract-role-aria/input.html
@@ -0,0 +1 @@
+<div role="doc-abstract">This work examines the maintenance of coastal lighthouses in the 19th century.</div>
diff --git a/fixtures/abstract-role-aria/meta.json b/fixtures/abstract-role-aria/meta.json
new file mode 100644
index 0000000..45aba7b
--- /dev/null
+++ b/fixtures/abstract-role-aria/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "abstract-role-aria",
+  "description": "abstract role via explicit ARIA role=\"doc-abstract\"",
+  "role": "abstract",
+  "rolesCovered": [
+    "abstract"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/abstract-role-aria/utterances.json b/fixtures/abstract-role-aria/utterances.json
new file mode 100644
index 0000000..015e7d5
--- /dev/null
+++ b/fixtures/abstract-role-aria/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "This work examines the maintenance of coastal lighthouses in the 19th century."
+  }
+]
diff --git a/fixtures/acknowledgments-epub-type/gnd.json b/fixtures/acknowledgments-epub-type/gnd.json
new file mode 100644
index 0000000..9d8600b
--- /dev/null
+++ b/fixtures/acknowledgments-epub-type/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "acknowledgments"
+  ],
+  "text": "The author thanks the keepers of Fastnet Rock for their recollections."
+}
diff --git a/fixtures/acknowledgments-epub-type/input.html b/fixtures/acknowledgments-epub-type/input.html
new file mode 100644
index 0000000..46d3cb1
--- /dev/null
+++ b/fixtures/acknowledgments-epub-type/input.html
@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops">
+<head>
+<meta charset="utf-8"/>
+<title>Fixture</title>
+</head>
+<body>
+<div epub:type="acknowledgments">The author thanks the keepers of Fastnet Rock for their recollections.</div>
+</body>
+</html>
diff --git a/fixtures/acknowledgments-epub-type/meta.json b/fixtures/acknowledgments-epub-type/meta.json
new file mode 100644
index 0000000..15c6295
--- /dev/null
+++ b/fixtures/acknowledgments-epub-type/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "acknowledgments-epub-type",
+  "description": "acknowledgments role via epub:type=\"acknowledgments\"",
+  "role": "acknowledgments",
+  "rolesCovered": [
+    "acknowledgments"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "document"
+}
diff --git a/fixtures/acknowledgments-epub-type/utterances.json b/fixtures/acknowledgments-epub-type/utterances.json
new file mode 100644
index 0000000..f39975a
--- /dev/null
+++ b/fixtures/acknowledgments-epub-type/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "The author thanks the keepers of Fastnet Rock for their recollections."
+  }
+]
diff --git a/fixtures/acknowledgments-role-aria/gnd.json b/fixtures/acknowledgments-role-aria/gnd.json
new file mode 100644
index 0000000..9d8600b
--- /dev/null
+++ b/fixtures/acknowledgments-role-aria/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "acknowledgments"
+  ],
+  "text": "The author thanks the keepers of Fastnet Rock for their recollections."
+}
diff --git a/fixtures/acknowledgments-role-aria/input.html b/fixtures/acknowledgments-role-aria/input.html
new file mode 100644
index 0000000..bf0e73c
--- /dev/null
+++ b/fixtures/acknowledgments-role-aria/input.html
@@ -0,0 +1 @@
+<div role="doc-acknowledgments">The author thanks the keepers of Fastnet Rock for their recollections.</div>
diff --git a/fixtures/acknowledgments-role-aria/meta.json b/fixtures/acknowledgments-role-aria/meta.json
new file mode 100644
index 0000000..e4193fa
--- /dev/null
+++ b/fixtures/acknowledgments-role-aria/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "acknowledgments-role-aria",
+  "description": "acknowledgments role via explicit ARIA role=\"doc-acknowledgments\"",
+  "role": "acknowledgments",
+  "rolesCovered": [
+    "acknowledgments"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/acknowledgments-role-aria/utterances.json b/fixtures/acknowledgments-role-aria/utterances.json
new file mode 100644
index 0000000..f39975a
--- /dev/null
+++ b/fixtures/acknowledgments-role-aria/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "The author thanks the keepers of Fastnet Rock for their recollections."
+  }
+]
diff --git a/fixtures/afterword-epub-type/gnd.json b/fixtures/afterword-epub-type/gnd.json
new file mode 100644
index 0000000..9757a46
--- /dev/null
+++ b/fixtures/afterword-epub-type/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "afterword"
+  ],
+  "text": "Years later, the last lighthouse keeper reflects on automation."
+}
diff --git a/fixtures/afterword-epub-type/input.html b/fixtures/afterword-epub-type/input.html
new file mode 100644
index 0000000..ef1feee
--- /dev/null
+++ b/fixtures/afterword-epub-type/input.html
@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops">
+<head>
+<meta charset="utf-8"/>
+<title>Fixture</title>
+</head>
+<body>
+<div epub:type="afterword">Years later, the last lighthouse keeper reflects on automation.</div>
+</body>
+</html>
diff --git a/fixtures/afterword-epub-type/meta.json b/fixtures/afterword-epub-type/meta.json
new file mode 100644
index 0000000..35352e4
--- /dev/null
+++ b/fixtures/afterword-epub-type/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "afterword-epub-type",
+  "description": "afterword role via epub:type=\"afterword\"",
+  "role": "afterword",
+  "rolesCovered": [
+    "afterword"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "document"
+}
diff --git a/fixtures/afterword-epub-type/utterances.json b/fixtures/afterword-epub-type/utterances.json
new file mode 100644
index 0000000..26e238c
--- /dev/null
+++ b/fixtures/afterword-epub-type/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "Years later, the last lighthouse keeper reflects on automation."
+  }
+]
diff --git a/fixtures/afterword-role-aria/gnd.json b/fixtures/afterword-role-aria/gnd.json
new file mode 100644
index 0000000..9757a46
--- /dev/null
+++ b/fixtures/afterword-role-aria/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "afterword"
+  ],
+  "text": "Years later, the last lighthouse keeper reflects on automation."
+}
diff --git a/fixtures/afterword-role-aria/input.html b/fixtures/afterword-role-aria/input.html
new file mode 100644
index 0000000..202a6dd
--- /dev/null
+++ b/fixtures/afterword-role-aria/input.html
@@ -0,0 +1 @@
+<div role="doc-afterword">Years later, the last lighthouse keeper reflects on automation.</div>
diff --git a/fixtures/afterword-role-aria/meta.json b/fixtures/afterword-role-aria/meta.json
new file mode 100644
index 0000000..c42964d
--- /dev/null
+++ b/fixtures/afterword-role-aria/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "afterword-role-aria",
+  "description": "afterword role via explicit ARIA role=\"doc-afterword\"",
+  "role": "afterword",
+  "rolesCovered": [
+    "afterword"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/afterword-role-aria/utterances.json b/fixtures/afterword-role-aria/utterances.json
new file mode 100644
index 0000000..26e238c
--- /dev/null
+++ b/fixtures/afterword-role-aria/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "Years later, the last lighthouse keeper reflects on automation."
+  }
+]
diff --git a/fixtures/appendix-epub-type/gnd.json b/fixtures/appendix-epub-type/gnd.json
new file mode 100644
index 0000000..4592a4a
--- /dev/null
+++ b/fixtures/appendix-epub-type/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "appendix"
+  ],
+  "text": "A table of lighthouse construction dates referenced in the text."
+}
diff --git a/fixtures/appendix-epub-type/input.html b/fixtures/appendix-epub-type/input.html
new file mode 100644
index 0000000..506f105
--- /dev/null
+++ b/fixtures/appendix-epub-type/input.html
@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops">
+<head>
+<meta charset="utf-8"/>
+<title>Fixture</title>
+</head>
+<body>
+<section epub:type="appendix">A table of lighthouse construction dates referenced in the text.</section>
+</body>
+</html>
diff --git a/fixtures/appendix-epub-type/meta.json b/fixtures/appendix-epub-type/meta.json
new file mode 100644
index 0000000..d52c678
--- /dev/null
+++ b/fixtures/appendix-epub-type/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "appendix-epub-type",
+  "description": "appendix role via epub:type=\"appendix\" on a <section>",
+  "role": "appendix",
+  "rolesCovered": [
+    "appendix"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "document"
+}
diff --git a/fixtures/appendix-epub-type/utterances.json b/fixtures/appendix-epub-type/utterances.json
new file mode 100644
index 0000000..dddcc84
--- /dev/null
+++ b/fixtures/appendix-epub-type/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "A table of lighthouse construction dates referenced in the text."
+  }
+]
diff --git a/fixtures/appendix-role-aria/gnd.json b/fixtures/appendix-role-aria/gnd.json
new file mode 100644
index 0000000..4592a4a
--- /dev/null
+++ b/fixtures/appendix-role-aria/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "appendix"
+  ],
+  "text": "A table of lighthouse construction dates referenced in the text."
+}
diff --git a/fixtures/appendix-role-aria/input.html b/fixtures/appendix-role-aria/input.html
new file mode 100644
index 0000000..36b3dbc
--- /dev/null
+++ b/fixtures/appendix-role-aria/input.html
@@ -0,0 +1 @@
+<div role="doc-appendix">A table of lighthouse construction dates referenced in the text.</div>
diff --git a/fixtures/appendix-role-aria/meta.json b/fixtures/appendix-role-aria/meta.json
new file mode 100644
index 0000000..66b3bd7
--- /dev/null
+++ b/fixtures/appendix-role-aria/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "appendix-role-aria",
+  "description": "appendix role via explicit ARIA role=\"doc-appendix\"",
+  "role": "appendix",
+  "rolesCovered": [
+    "appendix"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/appendix-role-aria/utterances.json b/fixtures/appendix-role-aria/utterances.json
new file mode 100644
index 0000000..dddcc84
--- /dev/null
+++ b/fixtures/appendix-role-aria/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "A table of lighthouse construction dates referenced in the text."
+  }
+]
diff --git a/fixtures/article-html-native/gnd.json b/fixtures/article-html-native/gnd.json
new file mode 100644
index 0000000..d339afb
--- /dev/null
+++ b/fixtures/article-html-native/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "article"
+  ],
+  "text": "A self-contained article about lighthouse keeping."
+}
diff --git a/fixtures/article-html-native/input.html b/fixtures/article-html-native/input.html
new file mode 100644
index 0000000..3ae1796
--- /dev/null
+++ b/fixtures/article-html-native/input.html
@@ -0,0 +1 @@
+<article>A self-contained article about lighthouse keeping.</article>
diff --git a/fixtures/article-html-native/meta.json b/fixtures/article-html-native/meta.json
new file mode 100644
index 0000000..79727e5
--- /dev/null
+++ b/fixtures/article-html-native/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "article-html-native",
+  "description": "article role via native <article> element",
+  "role": "article",
+  "rolesCovered": [
+    "article"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/article-html-native/utterances.json b/fixtures/article-html-native/utterances.json
new file mode 100644
index 0000000..24789d1
--- /dev/null
+++ b/fixtures/article-html-native/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "A self-contained article about lighthouse keeping."
+  }
+]
diff --git a/fixtures/aside-html-native/gnd.json b/fixtures/aside-html-native/gnd.json
new file mode 100644
index 0000000..1b18c22
--- /dev/null
+++ b/fixtures/aside-html-native/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "aside"
+  ],
+  "text": "By the way, lighthouses were once staffed around the clock."
+}
diff --git a/fixtures/aside-html-native/input.html b/fixtures/aside-html-native/input.html
new file mode 100644
index 0000000..a346f18
--- /dev/null
+++ b/fixtures/aside-html-native/input.html
@@ -0,0 +1 @@
+<aside>By the way, lighthouses were once staffed around the clock.</aside>
diff --git a/fixtures/aside-html-native/meta.json b/fixtures/aside-html-native/meta.json
new file mode 100644
index 0000000..87272cc
--- /dev/null
+++ b/fixtures/aside-html-native/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "aside-html-native",
+  "description": "aside role via native <aside> element",
+  "role": "aside",
+  "rolesCovered": [
+    "aside"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/aside-html-native/utterances.json b/fixtures/aside-html-native/utterances.json
new file mode 100644
index 0000000..37454b2
--- /dev/null
+++ b/fixtures/aside-html-native/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "By the way, lighthouses were once staffed around the clock."
+  }
+]
diff --git a/fixtures/audio-html-native/gnd.json b/fixtures/audio-html-native/gnd.json
new file mode 100644
index 0000000..5c930bf
--- /dev/null
+++ b/fixtures/audio-html-native/gnd.json
@@ -0,0 +1,7 @@
+{
+  "role": [
+    "audio"
+  ],
+  "audioref": "foghorn-recording.mp3",
+  "description": "Foghorn recording from the 1962 restoration"
+}
diff --git a/fixtures/audio-html-native/input.html b/fixtures/audio-html-native/input.html
new file mode 100644
index 0000000..75f0614
--- /dev/null
+++ b/fixtures/audio-html-native/input.html
@@ -0,0 +1 @@
+<audio src="foghorn-recording.mp3" controls aria-label="Foghorn recording from the 1962 restoration"></audio>
diff --git a/fixtures/audio-html-native/meta.json b/fixtures/audio-html-native/meta.json
new file mode 100644
index 0000000..c9ff551
--- /dev/null
+++ b/fixtures/audio-html-native/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "audio-html-native",
+  "description": "audio role via native <audio src> element, with an aria-label as the accessible description",
+  "role": "audio",
+  "rolesCovered": [
+    "audio"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/audio-html-native/utterances.json b/fixtures/audio-html-native/utterances.json
new file mode 100644
index 0000000..43698a2
--- /dev/null
+++ b/fixtures/audio-html-native/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "Foghorn recording from the 1962 restoration"
+  }
+]
diff --git a/fixtures/backlink-epub-type/gnd.json b/fixtures/backlink-epub-type/gnd.json
new file mode 100644
index 0000000..d9653e3
--- /dev/null
+++ b/fixtures/backlink-epub-type/gnd.json
@@ -0,0 +1,7 @@
+{
+  "role": [
+    "backlink"
+  ],
+  "text": "Return to reference",
+  "textref": "#ref1"
+}
diff --git a/fixtures/backlink-epub-type/input.html b/fixtures/backlink-epub-type/input.html
new file mode 100644
index 0000000..79c76f9
--- /dev/null
+++ b/fixtures/backlink-epub-type/input.html
@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops">
+<head>
+<meta charset="utf-8"/>
+<title>Fixture</title>
+</head>
+<body>
+<a href="#ref1" epub:type="backlink">Return to reference</a>
+</body>
+</html>
diff --git a/fixtures/backlink-epub-type/meta.json b/fixtures/backlink-epub-type/meta.json
new file mode 100644
index 0000000..48c377e
--- /dev/null
+++ b/fixtures/backlink-epub-type/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "backlink-epub-type",
+  "description": "backlink role via epub:type=\"backlink\" on an <a href>",
+  "role": "backlink",
+  "rolesCovered": [
+    "backlink"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "document"
+}
diff --git a/fixtures/backlink-epub-type/utterances.json b/fixtures/backlink-epub-type/utterances.json
new file mode 100644
index 0000000..a422901
--- /dev/null
+++ b/fixtures/backlink-epub-type/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "Return to reference"
+  }
+]
diff --git a/fixtures/backlink-role-aria/gnd.json b/fixtures/backlink-role-aria/gnd.json
new file mode 100644
index 0000000..d9653e3
--- /dev/null
+++ b/fixtures/backlink-role-aria/gnd.json
@@ -0,0 +1,7 @@
+{
+  "role": [
+    "backlink"
+  ],
+  "text": "Return to reference",
+  "textref": "#ref1"
+}
diff --git a/fixtures/backlink-role-aria/input.html b/fixtures/backlink-role-aria/input.html
new file mode 100644
index 0000000..f0fc32f
--- /dev/null
+++ b/fixtures/backlink-role-aria/input.html
@@ -0,0 +1 @@
+<a href="#ref1" role="doc-backlink">Return to reference</a>
diff --git a/fixtures/backlink-role-aria/meta.json b/fixtures/backlink-role-aria/meta.json
new file mode 100644
index 0000000..eeb3841
--- /dev/null
+++ b/fixtures/backlink-role-aria/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "backlink-role-aria",
+  "description": "backlink role via explicit ARIA role=\"doc-backlink\" on an <a href>",
+  "role": "backlink",
+  "rolesCovered": [
+    "backlink"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/backlink-role-aria/utterances.json b/fixtures/backlink-role-aria/utterances.json
new file mode 100644
index 0000000..a422901
--- /dev/null
+++ b/fixtures/backlink-role-aria/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "Return to reference"
+  }
+]
diff --git a/fixtures/bibliography-epub-type/gnd.json b/fixtures/bibliography-epub-type/gnd.json
new file mode 100644
index 0000000..8f58379
--- /dev/null
+++ b/fixtures/bibliography-epub-type/gnd.json
@@ -0,0 +1,26 @@
+{
+  "role": [
+    "bibliography"
+  ],
+  "children": [
+    {
+      "role": [
+        "list"
+      ],
+      "children": [
+        {
+          "role": [
+            "listItem"
+          ],
+          "text": "Smith, J. Lighthouses of the Atlantic. 1988."
+        },
+        {
+          "role": [
+            "listItem"
+          ],
+          "text": "Doe, A. Coastal Illumination. 1975."
+        }
+      ]
+    }
+  ]
+}
diff --git a/fixtures/bibliography-epub-type/input.html b/fixtures/bibliography-epub-type/input.html
new file mode 100644
index 0000000..938d724
--- /dev/null
+++ b/fixtures/bibliography-epub-type/input.html
@@ -0,0 +1,16 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops">
+<head>
+<meta charset="utf-8"/>
+<title>Fixture</title>
+</head>
+<body>
+<section epub:type="bibliography">
+  <ol>
+    <li>Smith, J. Lighthouses of the Atlantic. 1988.</li>
+    <li>Doe, A. Coastal Illumination. 1975.</li>
+  </ol>
+</section>
+</body>
+</html>
diff --git a/fixtures/bibliography-epub-type/meta.json b/fixtures/bibliography-epub-type/meta.json
new file mode 100644
index 0000000..5523b78
--- /dev/null
+++ b/fixtures/bibliography-epub-type/meta.json
@@ -0,0 +1,12 @@
+{
+  "id": "bibliography-epub-type",
+  "description": "A bibliography list of cited references, via epub:type=\"bibliography\" on a <section>",
+  "role": "bibliography",
+  "rolesCovered": [
+    "bibliography",
+    "list",
+    "listItem"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "document"
+}
diff --git a/fixtures/bibliography-epub-type/utterances.json b/fixtures/bibliography-epub-type/utterances.json
new file mode 100644
index 0000000..c3778b6
--- /dev/null
+++ b/fixtures/bibliography-epub-type/utterances.json
@@ -0,0 +1,8 @@
+[
+  {
+    "text": "Smith, J. Lighthouses of the Atlantic. 1988."
+  },
+  {
+    "text": "Doe, A. Coastal Illumination. 1975."
+  }
+]
diff --git a/fixtures/bibliography-role-aria/gnd.json b/fixtures/bibliography-role-aria/gnd.json
new file mode 100644
index 0000000..8f58379
--- /dev/null
+++ b/fixtures/bibliography-role-aria/gnd.json
@@ -0,0 +1,26 @@
+{
+  "role": [
+    "bibliography"
+  ],
+  "children": [
+    {
+      "role": [
+        "list"
+      ],
+      "children": [
+        {
+          "role": [
+            "listItem"
+          ],
+          "text": "Smith, J. Lighthouses of the Atlantic. 1988."
+        },
+        {
+          "role": [
+            "listItem"
+          ],
+          "text": "Doe, A. Coastal Illumination. 1975."
+        }
+      ]
+    }
+  ]
+}
diff --git a/fixtures/bibliography-role-aria/input.html b/fixtures/bibliography-role-aria/input.html
new file mode 100644
index 0000000..50fe22f
--- /dev/null
+++ b/fixtures/bibliography-role-aria/input.html
@@ -0,0 +1,6 @@
+<div role="doc-bibliography">
+  <ol>
+    <li>Smith, J. Lighthouses of the Atlantic. 1988.</li>
+    <li>Doe, A. Coastal Illumination. 1975.</li>
+  </ol>
+</div>
diff --git a/fixtures/bibliography-role-aria/meta.json b/fixtures/bibliography-role-aria/meta.json
new file mode 100644
index 0000000..16d22a8
--- /dev/null
+++ b/fixtures/bibliography-role-aria/meta.json
@@ -0,0 +1,12 @@
+{
+  "id": "bibliography-role-aria",
+  "description": "A bibliography list of cited references, via explicit ARIA role",
+  "role": "bibliography",
+  "rolesCovered": [
+    "bibliography",
+    "list",
+    "listItem"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/bibliography-role-aria/utterances.json b/fixtures/bibliography-role-aria/utterances.json
new file mode 100644
index 0000000..c3778b6
--- /dev/null
+++ b/fixtures/bibliography-role-aria/utterances.json
@@ -0,0 +1,8 @@
+[
+  {
+    "text": "Smith, J. Lighthouses of the Atlantic. 1988."
+  },
+  {
+    "text": "Doe, A. Coastal Illumination. 1975."
+  }
+]
diff --git a/fixtures/biblioref-epub-type/gnd.json b/fixtures/biblioref-epub-type/gnd.json
new file mode 100644
index 0000000..b0a664f
--- /dev/null
+++ b/fixtures/biblioref-epub-type/gnd.json
@@ -0,0 +1,7 @@
+{
+  "role": [
+    "biblioref"
+  ],
+  "text": "See Smith, 1988",
+  "textref": "#smith1988"
+}
diff --git a/fixtures/biblioref-epub-type/input.html b/fixtures/biblioref-epub-type/input.html
new file mode 100644
index 0000000..4490774
--- /dev/null
+++ b/fixtures/biblioref-epub-type/input.html
@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops">
+<head>
+<meta charset="utf-8"/>
+<title>Fixture</title>
+</head>
+<body>
+<a href="#smith1988" epub:type="biblioref">See Smith, 1988</a>
+</body>
+</html>
diff --git a/fixtures/biblioref-epub-type/meta.json b/fixtures/biblioref-epub-type/meta.json
new file mode 100644
index 0000000..d4049c2
--- /dev/null
+++ b/fixtures/biblioref-epub-type/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "biblioref-epub-type",
+  "description": "biblioref role via epub:type=\"biblioref\" on an <a href>",
+  "role": "biblioref",
+  "rolesCovered": [
+    "biblioref"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "document"
+}
diff --git a/fixtures/biblioref-epub-type/utterances.json b/fixtures/biblioref-epub-type/utterances.json
new file mode 100644
index 0000000..534be16
--- /dev/null
+++ b/fixtures/biblioref-epub-type/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "See Smith, 1988"
+  }
+]
diff --git a/fixtures/biblioref-role-aria/gnd.json b/fixtures/biblioref-role-aria/gnd.json
new file mode 100644
index 0000000..b0a664f
--- /dev/null
+++ b/fixtures/biblioref-role-aria/gnd.json
@@ -0,0 +1,7 @@
+{
+  "role": [
+    "biblioref"
+  ],
+  "text": "See Smith, 1988",
+  "textref": "#smith1988"
+}
diff --git a/fixtures/biblioref-role-aria/input.html b/fixtures/biblioref-role-aria/input.html
new file mode 100644
index 0000000..270fdcf
--- /dev/null
+++ b/fixtures/biblioref-role-aria/input.html
@@ -0,0 +1 @@
+<a href="#smith1988" role="doc-biblioref">See Smith, 1988</a>
diff --git a/fixtures/biblioref-role-aria/meta.json b/fixtures/biblioref-role-aria/meta.json
new file mode 100644
index 0000000..fc52583
--- /dev/null
+++ b/fixtures/biblioref-role-aria/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "biblioref-role-aria",
+  "description": "biblioref role via explicit ARIA role=\"doc-biblioref\" on an <a href>",
+  "role": "biblioref",
+  "rolesCovered": [
+    "biblioref"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/biblioref-role-aria/utterances.json b/fixtures/biblioref-role-aria/utterances.json
new file mode 100644
index 0000000..534be16
--- /dev/null
+++ b/fixtures/biblioref-role-aria/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "See Smith, 1988"
+  }
+]
diff --git a/fixtures/blockquote-html-native/gnd.json b/fixtures/blockquote-html-native/gnd.json
new file mode 100644
index 0000000..a29c5db
--- /dev/null
+++ b/fixtures/blockquote-html-native/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "blockquote"
+  ],
+  "text": "To be, or not to be, that is the question."
+}
diff --git a/fixtures/blockquote-html-native/input.html b/fixtures/blockquote-html-native/input.html
new file mode 100644
index 0000000..6118c96
--- /dev/null
+++ b/fixtures/blockquote-html-native/input.html
@@ -0,0 +1 @@
+<blockquote>To be, or not to be, that is the question.</blockquote>
diff --git a/fixtures/blockquote-html-native/meta.json b/fixtures/blockquote-html-native/meta.json
new file mode 100644
index 0000000..86532e8
--- /dev/null
+++ b/fixtures/blockquote-html-native/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "blockquote-html-native",
+  "description": "blockquote role via native <blockquote> element",
+  "role": "blockquote",
+  "rolesCovered": [
+    "blockquote"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/blockquote-html-native/utterances.json b/fixtures/blockquote-html-native/utterances.json
new file mode 100644
index 0000000..ac4c2e2
--- /dev/null
+++ b/fixtures/blockquote-html-native/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "To be, or not to be, that is the question."
+  }
+]
diff --git a/fixtures/body-html-native/gnd.json b/fixtures/body-html-native/gnd.json
new file mode 100644
index 0000000..b718e78
--- /dev/null
+++ b/fixtures/body-html-native/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "body"
+  ],
+  "text": "The full content of the document."
+}
diff --git a/fixtures/body-html-native/input.html b/fixtures/body-html-native/input.html
new file mode 100644
index 0000000..e1cc5e9
--- /dev/null
+++ b/fixtures/body-html-native/input.html
@@ -0,0 +1 @@
+<body>The full content of the document.</body>
diff --git a/fixtures/body-html-native/meta.json b/fixtures/body-html-native/meta.json
new file mode 100644
index 0000000..6817961
--- /dev/null
+++ b/fixtures/body-html-native/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "body-html-native",
+  "description": "body role via native <body> element",
+  "role": "body",
+  "rolesCovered": [
+    "body"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/body-html-native/utterances.json b/fixtures/body-html-native/utterances.json
new file mode 100644
index 0000000..570855c
--- /dev/null
+++ b/fixtures/body-html-native/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "The full content of the document."
+  }
+]
diff --git a/fixtures/chapter-epub-type/gnd.json b/fixtures/chapter-epub-type/gnd.json
new file mode 100644
index 0000000..9e95612
--- /dev/null
+++ b/fixtures/chapter-epub-type/gnd.json
@@ -0,0 +1,13 @@
+{
+  "role": [
+    "chapter"
+  ],
+  "children": [
+    {
+      "role": [
+        "heading1"
+      ],
+      "text": "Title of the chapter"
+    }
+  ]
+}
diff --git a/fixtures/chapter-epub-type/input.html b/fixtures/chapter-epub-type/input.html
new file mode 100644
index 0000000..6b2e130
--- /dev/null
+++ b/fixtures/chapter-epub-type/input.html
@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops">
+<head>
+<meta charset="utf-8"/>
+<title>Fixture</title>
+</head>
+<body>
+<section epub:type="chapter">
+  <h1>Title of the chapter</h1>
+</section>
+</body>
+</html>
diff --git a/fixtures/chapter-epub-type/meta.json b/fixtures/chapter-epub-type/meta.json
new file mode 100644
index 0000000..7cee514
--- /dev/null
+++ b/fixtures/chapter-epub-type/meta.json
@@ -0,0 +1,11 @@
+{
+  "id": "chapter-epub-type",
+  "description": "chapter role via epub:type=\"chapter\", containing a heading",
+  "role": "chapter",
+  "rolesCovered": [
+    "chapter",
+    "heading1"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/tree/main/examples/read-aloud#sections-and-headers",
+  "inputKind": "document"
+}
diff --git a/fixtures/chapter-epub-type/utterances.json b/fixtures/chapter-epub-type/utterances.json
new file mode 100644
index 0000000..3f67223
--- /dev/null
+++ b/fixtures/chapter-epub-type/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "Title of the chapter"
+  }
+]
diff --git a/fixtures/chapter-role-aria/gnd.json b/fixtures/chapter-role-aria/gnd.json
new file mode 100644
index 0000000..9e95612
--- /dev/null
+++ b/fixtures/chapter-role-aria/gnd.json
@@ -0,0 +1,13 @@
+{
+  "role": [
+    "chapter"
+  ],
+  "children": [
+    {
+      "role": [
+        "heading1"
+      ],
+      "text": "Title of the chapter"
+    }
+  ]
+}
diff --git a/fixtures/chapter-role-aria/input.html b/fixtures/chapter-role-aria/input.html
new file mode 100644
index 0000000..31bcf7d
--- /dev/null
+++ b/fixtures/chapter-role-aria/input.html
@@ -0,0 +1,3 @@
+<section role="doc-chapter">
+  <h1>Title of the chapter</h1>
+</section>
diff --git a/fixtures/chapter-role-aria/meta.json b/fixtures/chapter-role-aria/meta.json
new file mode 100644
index 0000000..338bd7a
--- /dev/null
+++ b/fixtures/chapter-role-aria/meta.json
@@ -0,0 +1,11 @@
+{
+  "id": "chapter-role-aria",
+  "description": "chapter role via explicit ARIA role=\"doc-chapter\", containing a heading",
+  "role": "chapter",
+  "rolesCovered": [
+    "chapter",
+    "heading1"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/chapter-role-aria/utterances.json b/fixtures/chapter-role-aria/utterances.json
new file mode 100644
index 0000000..3f67223
--- /dev/null
+++ b/fixtures/chapter-role-aria/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "Title of the chapter"
+  }
+]
diff --git a/fixtures/colophon-epub-type/gnd.json b/fixtures/colophon-epub-type/gnd.json
new file mode 100644
index 0000000..9cc935c
--- /dev/null
+++ b/fixtures/colophon-epub-type/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "colophon"
+  ],
+  "text": "Set in Georgia, 11pt, on recycled paper."
+}
diff --git a/fixtures/colophon-epub-type/input.html b/fixtures/colophon-epub-type/input.html
new file mode 100644
index 0000000..435bfdd
--- /dev/null
+++ b/fixtures/colophon-epub-type/input.html
@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops">
+<head>
+<meta charset="utf-8"/>
+<title>Fixture</title>
+</head>
+<body>
+<div epub:type="colophon">Set in Georgia, 11pt, on recycled paper.</div>
+</body>
+</html>
diff --git a/fixtures/colophon-epub-type/meta.json b/fixtures/colophon-epub-type/meta.json
new file mode 100644
index 0000000..da2f155
--- /dev/null
+++ b/fixtures/colophon-epub-type/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "colophon-epub-type",
+  "description": "colophon role via epub:type=\"colophon\"",
+  "role": "colophon",
+  "rolesCovered": [
+    "colophon"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "document"
+}
diff --git a/fixtures/colophon-epub-type/utterances.json b/fixtures/colophon-epub-type/utterances.json
new file mode 100644
index 0000000..1123dab
--- /dev/null
+++ b/fixtures/colophon-epub-type/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "Set in Georgia, 11pt, on recycled paper."
+  }
+]
diff --git a/fixtures/colophon-role-aria/gnd.json b/fixtures/colophon-role-aria/gnd.json
new file mode 100644
index 0000000..9cc935c
--- /dev/null
+++ b/fixtures/colophon-role-aria/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "colophon"
+  ],
+  "text": "Set in Georgia, 11pt, on recycled paper."
+}
diff --git a/fixtures/colophon-role-aria/input.html b/fixtures/colophon-role-aria/input.html
new file mode 100644
index 0000000..23ef338
--- /dev/null
+++ b/fixtures/colophon-role-aria/input.html
@@ -0,0 +1 @@
+<div role="doc-colophon">Set in Georgia, 11pt, on recycled paper.</div>
diff --git a/fixtures/colophon-role-aria/meta.json b/fixtures/colophon-role-aria/meta.json
new file mode 100644
index 0000000..3cbf264
--- /dev/null
+++ b/fixtures/colophon-role-aria/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "colophon-role-aria",
+  "description": "colophon role via explicit ARIA role=\"doc-colophon\"",
+  "role": "colophon",
+  "rolesCovered": [
+    "colophon"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/colophon-role-aria/utterances.json b/fixtures/colophon-role-aria/utterances.json
new file mode 100644
index 0000000..1123dab
--- /dev/null
+++ b/fixtures/colophon-role-aria/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "Set in Georgia, 11pt, on recycled paper."
+  }
+]
diff --git a/fixtures/complementary-role-aria/gnd.json b/fixtures/complementary-role-aria/gnd.json
new file mode 100644
index 0000000..8478243
--- /dev/null
+++ b/fixtures/complementary-role-aria/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "complementary"
+  ],
+  "text": "A supporting note related to the main content."
+}
diff --git a/fixtures/complementary-role-aria/input.html b/fixtures/complementary-role-aria/input.html
new file mode 100644
index 0000000..ea9e94e
--- /dev/null
+++ b/fixtures/complementary-role-aria/input.html
@@ -0,0 +1 @@
+<div role="complementary">A supporting note related to the main content.</div>
diff --git a/fixtures/complementary-role-aria/meta.json b/fixtures/complementary-role-aria/meta.json
new file mode 100644
index 0000000..eaa602d
--- /dev/null
+++ b/fixtures/complementary-role-aria/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "complementary-role-aria",
+  "description": "complementary role via explicit ARIA role=\"complementary\"",
+  "role": "complementary",
+  "rolesCovered": [
+    "complementary"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/complementary-role-aria/utterances.json b/fixtures/complementary-role-aria/utterances.json
new file mode 100644
index 0000000..662441f
--- /dev/null
+++ b/fixtures/complementary-role-aria/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "A supporting note related to the main content."
+  }
+]
diff --git a/fixtures/conclusion-epub-type/gnd.json b/fixtures/conclusion-epub-type/gnd.json
new file mode 100644
index 0000000..69ea621
--- /dev/null
+++ b/fixtures/conclusion-epub-type/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "conclusion"
+  ],
+  "text": "Lighthouses remain a symbol of safe passage."
+}
diff --git a/fixtures/conclusion-epub-type/input.html b/fixtures/conclusion-epub-type/input.html
new file mode 100644
index 0000000..62ff949
--- /dev/null
+++ b/fixtures/conclusion-epub-type/input.html
@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops">
+<head>
+<meta charset="utf-8"/>
+<title>Fixture</title>
+</head>
+<body>
+<div epub:type="conclusion">Lighthouses remain a symbol of safe passage.</div>
+</body>
+</html>
diff --git a/fixtures/conclusion-epub-type/meta.json b/fixtures/conclusion-epub-type/meta.json
new file mode 100644
index 0000000..c27fd77
--- /dev/null
+++ b/fixtures/conclusion-epub-type/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "conclusion-epub-type",
+  "description": "conclusion role via epub:type=\"conclusion\"",
+  "role": "conclusion",
+  "rolesCovered": [
+    "conclusion"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "document"
+}
diff --git a/fixtures/conclusion-epub-type/utterances.json b/fixtures/conclusion-epub-type/utterances.json
new file mode 100644
index 0000000..209d60e
--- /dev/null
+++ b/fixtures/conclusion-epub-type/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "Lighthouses remain a symbol of safe passage."
+  }
+]
diff --git a/fixtures/conclusion-role-aria/gnd.json b/fixtures/conclusion-role-aria/gnd.json
new file mode 100644
index 0000000..69ea621
--- /dev/null
+++ b/fixtures/conclusion-role-aria/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "conclusion"
+  ],
+  "text": "Lighthouses remain a symbol of safe passage."
+}
diff --git a/fixtures/conclusion-role-aria/input.html b/fixtures/conclusion-role-aria/input.html
new file mode 100644
index 0000000..35a9c0d
--- /dev/null
+++ b/fixtures/conclusion-role-aria/input.html
@@ -0,0 +1 @@
+<div role="doc-conclusion">Lighthouses remain a symbol of safe passage.</div>
diff --git a/fixtures/conclusion-role-aria/meta.json b/fixtures/conclusion-role-aria/meta.json
new file mode 100644
index 0000000..f236565
--- /dev/null
+++ b/fixtures/conclusion-role-aria/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "conclusion-role-aria",
+  "description": "conclusion role via explicit ARIA role=\"doc-conclusion\"",
+  "role": "conclusion",
+  "rolesCovered": [
+    "conclusion"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/conclusion-role-aria/utterances.json b/fixtures/conclusion-role-aria/utterances.json
new file mode 100644
index 0000000..209d60e
--- /dev/null
+++ b/fixtures/conclusion-role-aria/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "Lighthouses remain a symbol of safe passage."
+  }
+]
diff --git a/fixtures/cover-epub-type/gnd.json b/fixtures/cover-epub-type/gnd.json
new file mode 100644
index 0000000..7ca55ac
--- /dev/null
+++ b/fixtures/cover-epub-type/gnd.json
@@ -0,0 +1,14 @@
+{
+  "role": [
+    "cover"
+  ],
+  "children": [
+    {
+      "role": [
+        "image"
+      ],
+      "imgref": "cover.jpg",
+      "description": "Lighthouses of the Atlantic, by J. Smith"
+    }
+  ]
+}
diff --git a/fixtures/cover-epub-type/input.html b/fixtures/cover-epub-type/input.html
new file mode 100644
index 0000000..b8a7027
--- /dev/null
+++ b/fixtures/cover-epub-type/input.html
@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops">
+<head>
+<meta charset="utf-8"/>
+<title>Fixture</title>
+</head>
+<body>
+<section epub:type="cover">
+  <img src="cover.jpg" alt="Lighthouses of the Atlantic, by J. Smith"/>
+</section>
+</body>
+</html>
diff --git a/fixtures/cover-epub-type/meta.json b/fixtures/cover-epub-type/meta.json
new file mode 100644
index 0000000..08a28a1
--- /dev/null
+++ b/fixtures/cover-epub-type/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "cover-epub-type",
+  "description": "cover role via epub:type=\"cover\" on a <section> wrapping the cover image",
+  "role": "cover",
+  "rolesCovered": [
+    "cover"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "document"
+}
diff --git a/fixtures/cover-epub-type/utterances.json b/fixtures/cover-epub-type/utterances.json
new file mode 100644
index 0000000..9a0ddb4
--- /dev/null
+++ b/fixtures/cover-epub-type/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "Lighthouses of the Atlantic, by J. Smith"
+  }
+]
diff --git a/fixtures/cover-role-aria/gnd.json b/fixtures/cover-role-aria/gnd.json
new file mode 100644
index 0000000..c26f574
--- /dev/null
+++ b/fixtures/cover-role-aria/gnd.json
@@ -0,0 +1,7 @@
+{
+  "role": [
+    "cover"
+  ],
+  "imgref": "cover.jpg",
+  "description": "Lighthouses of the Atlantic, by J. Smith"
+}
diff --git a/fixtures/cover-role-aria/input.html b/fixtures/cover-role-aria/input.html
new file mode 100644
index 0000000..6182714
--- /dev/null
+++ b/fixtures/cover-role-aria/input.html
@@ -0,0 +1 @@
+<img src="cover.jpg" role="doc-cover" alt="Lighthouses of the Atlantic, by J. Smith">
diff --git a/fixtures/cover-role-aria/meta.json b/fixtures/cover-role-aria/meta.json
new file mode 100644
index 0000000..10d169b
--- /dev/null
+++ b/fixtures/cover-role-aria/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "cover-role-aria",
+  "description": "cover role via explicit ARIA role=\"doc-cover\" on an <img>",
+  "role": "cover",
+  "rolesCovered": [
+    "cover"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/cover-role-aria/utterances.json b/fixtures/cover-role-aria/utterances.json
new file mode 100644
index 0000000..9a0ddb4
--- /dev/null
+++ b/fixtures/cover-role-aria/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "Lighthouses of the Atlantic, by J. Smith"
+  }
+]
diff --git a/fixtures/credit-epub-type/gnd.json b/fixtures/credit-epub-type/gnd.json
new file mode 100644
index 0000000..39d48ed
--- /dev/null
+++ b/fixtures/credit-epub-type/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "credit"
+  ],
+  "text": "Cover photograph by A. Keeper."
+}
diff --git a/fixtures/credit-epub-type/input.html b/fixtures/credit-epub-type/input.html
new file mode 100644
index 0000000..235f3cf
--- /dev/null
+++ b/fixtures/credit-epub-type/input.html
@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops">
+<head>
+<meta charset="utf-8"/>
+<title>Fixture</title>
+</head>
+<body>
+<p><span epub:type="credit">Cover photograph by A. Keeper.</span></p>
+</body>
+</html>
diff --git a/fixtures/credit-epub-type/meta.json b/fixtures/credit-epub-type/meta.json
new file mode 100644
index 0000000..91019fa
--- /dev/null
+++ b/fixtures/credit-epub-type/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "credit-epub-type",
+  "description": "credit role via epub:type=\"credit\" on a <span>",
+  "role": "credit",
+  "rolesCovered": [
+    "credit"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "document"
+}
diff --git a/fixtures/credit-epub-type/utterances.json b/fixtures/credit-epub-type/utterances.json
new file mode 100644
index 0000000..f4f21e0
--- /dev/null
+++ b/fixtures/credit-epub-type/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "Cover photograph by A. Keeper."
+  }
+]
diff --git a/fixtures/credit-role-aria/gnd.json b/fixtures/credit-role-aria/gnd.json
new file mode 100644
index 0000000..39d48ed
--- /dev/null
+++ b/fixtures/credit-role-aria/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "credit"
+  ],
+  "text": "Cover photograph by A. Keeper."
+}
diff --git a/fixtures/credit-role-aria/input.html b/fixtures/credit-role-aria/input.html
new file mode 100644
index 0000000..ccfecfc
--- /dev/null
+++ b/fixtures/credit-role-aria/input.html
@@ -0,0 +1 @@
+<div role="doc-credit">Cover photograph by A. Keeper.</div>
diff --git a/fixtures/credit-role-aria/meta.json b/fixtures/credit-role-aria/meta.json
new file mode 100644
index 0000000..7600066
--- /dev/null
+++ b/fixtures/credit-role-aria/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "credit-role-aria",
+  "description": "credit role via explicit ARIA role=\"doc-credit\"",
+  "role": "credit",
+  "rolesCovered": [
+    "credit"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/credit-role-aria/utterances.json b/fixtures/credit-role-aria/utterances.json
new file mode 100644
index 0000000..f4f21e0
--- /dev/null
+++ b/fixtures/credit-role-aria/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "Cover photograph by A. Keeper."
+  }
+]
diff --git a/fixtures/credits-epub-type/gnd.json b/fixtures/credits-epub-type/gnd.json
new file mode 100644
index 0000000..b4d5979
--- /dev/null
+++ b/fixtures/credits-epub-type/gnd.json
@@ -0,0 +1,40 @@
+{
+  "role": [
+    "credits"
+  ],
+  "children": [
+    {
+      "role": [
+        "list"
+      ],
+      "children": [
+        {
+          "role": [
+            "listItem"
+          ],
+          "children": [
+            {
+              "role": [
+                "credit"
+              ],
+              "text": "Cover photograph by A. Keeper."
+            }
+          ]
+        },
+        {
+          "role": [
+            "listItem"
+          ],
+          "children": [
+            {
+              "role": [
+                "credit"
+              ],
+              "text": "Maps by B. Cartographer."
+            }
+          ]
+        }
+      ]
+    }
+  ]
+}
diff --git a/fixtures/credits-epub-type/input.html b/fixtures/credits-epub-type/input.html
new file mode 100644
index 0000000..124efde
--- /dev/null
+++ b/fixtures/credits-epub-type/input.html
@@ -0,0 +1,16 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops">
+<head>
+<meta charset="utf-8"/>
+<title>Fixture</title>
+</head>
+<body>
+<div epub:type="credits">
+  <ol>
+    <li><span epub:type="credit">Cover photograph by A. Keeper.</span></li>
+    <li><span epub:type="credit">Maps by B. Cartographer.</span></li>
+  </ol>
+</div>
+</body>
+</html>
diff --git a/fixtures/credits-epub-type/meta.json b/fixtures/credits-epub-type/meta.json
new file mode 100644
index 0000000..e0f2a61
--- /dev/null
+++ b/fixtures/credits-epub-type/meta.json
@@ -0,0 +1,13 @@
+{
+  "id": "credits-epub-type",
+  "description": "A collection of credits, via epub:type=\"credits\"; each entry is a <span epub:type=\"credit\">",
+  "role": "credits",
+  "rolesCovered": [
+    "credits",
+    "list",
+    "listItem",
+    "credit"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "document"
+}
diff --git a/fixtures/credits-epub-type/utterances.json b/fixtures/credits-epub-type/utterances.json
new file mode 100644
index 0000000..efc3de9
--- /dev/null
+++ b/fixtures/credits-epub-type/utterances.json
@@ -0,0 +1,8 @@
+[
+  {
+    "text": "Cover photograph by A. Keeper."
+  },
+  {
+    "text": "Maps by B. Cartographer."
+  }
+]
diff --git a/fixtures/credits-role-aria/gnd.json b/fixtures/credits-role-aria/gnd.json
new file mode 100644
index 0000000..b4d5979
--- /dev/null
+++ b/fixtures/credits-role-aria/gnd.json
@@ -0,0 +1,40 @@
+{
+  "role": [
+    "credits"
+  ],
+  "children": [
+    {
+      "role": [
+        "list"
+      ],
+      "children": [
+        {
+          "role": [
+            "listItem"
+          ],
+          "children": [
+            {
+              "role": [
+                "credit"
+              ],
+              "text": "Cover photograph by A. Keeper."
+            }
+          ]
+        },
+        {
+          "role": [
+            "listItem"
+          ],
+          "children": [
+            {
+              "role": [
+                "credit"
+              ],
+              "text": "Maps by B. Cartographer."
+            }
+          ]
+        }
+      ]
+    }
+  ]
+}
diff --git a/fixtures/credits-role-aria/input.html b/fixtures/credits-role-aria/input.html
new file mode 100644
index 0000000..bdc22da
--- /dev/null
+++ b/fixtures/credits-role-aria/input.html
@@ -0,0 +1,6 @@
+<div role="doc-credits">
+  <ol>
+    <li role="doc-credit">Cover photograph by A. Keeper.</li>
+    <li role="doc-credit">Maps by B. Cartographer.</li>
+  </ol>
+</div>
diff --git a/fixtures/credits-role-aria/meta.json b/fixtures/credits-role-aria/meta.json
new file mode 100644
index 0000000..b5221aa
--- /dev/null
+++ b/fixtures/credits-role-aria/meta.json
@@ -0,0 +1,13 @@
+{
+  "id": "credits-role-aria",
+  "description": "A collection of credits, via explicit ARIA role",
+  "role": "credits",
+  "rolesCovered": [
+    "credits",
+    "list",
+    "listItem",
+    "credit"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/credits-role-aria/utterances.json b/fixtures/credits-role-aria/utterances.json
new file mode 100644
index 0000000..efc3de9
--- /dev/null
+++ b/fixtures/credits-role-aria/utterances.json
@@ -0,0 +1,8 @@
+[
+  {
+    "text": "Cover photograph by A. Keeper."
+  },
+  {
+    "text": "Maps by B. Cartographer."
+  }
+]
diff --git a/fixtures/dedication-epub-type/gnd.json b/fixtures/dedication-epub-type/gnd.json
new file mode 100644
index 0000000..22cc2b2
--- /dev/null
+++ b/fixtures/dedication-epub-type/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "dedication"
+  ],
+  "text": "For every keeper who lit the lamp at dusk."
+}
diff --git a/fixtures/dedication-epub-type/input.html b/fixtures/dedication-epub-type/input.html
new file mode 100644
index 0000000..773b600
--- /dev/null
+++ b/fixtures/dedication-epub-type/input.html
@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops">
+<head>
+<meta charset="utf-8"/>
+<title>Fixture</title>
+</head>
+<body>
+<div epub:type="dedication">For every keeper who lit the lamp at dusk.</div>
+</body>
+</html>
diff --git a/fixtures/dedication-epub-type/meta.json b/fixtures/dedication-epub-type/meta.json
new file mode 100644
index 0000000..859f76b
--- /dev/null
+++ b/fixtures/dedication-epub-type/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "dedication-epub-type",
+  "description": "dedication role via epub:type=\"dedication\"",
+  "role": "dedication",
+  "rolesCovered": [
+    "dedication"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "document"
+}
diff --git a/fixtures/dedication-epub-type/utterances.json b/fixtures/dedication-epub-type/utterances.json
new file mode 100644
index 0000000..6a7ce00
--- /dev/null
+++ b/fixtures/dedication-epub-type/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "For every keeper who lit the lamp at dusk."
+  }
+]
diff --git a/fixtures/dedication-role-aria/gnd.json b/fixtures/dedication-role-aria/gnd.json
new file mode 100644
index 0000000..22cc2b2
--- /dev/null
+++ b/fixtures/dedication-role-aria/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "dedication"
+  ],
+  "text": "For every keeper who lit the lamp at dusk."
+}
diff --git a/fixtures/dedication-role-aria/input.html b/fixtures/dedication-role-aria/input.html
new file mode 100644
index 0000000..8892f27
--- /dev/null
+++ b/fixtures/dedication-role-aria/input.html
@@ -0,0 +1 @@
+<div role="doc-dedication">For every keeper who lit the lamp at dusk.</div>
diff --git a/fixtures/dedication-role-aria/meta.json b/fixtures/dedication-role-aria/meta.json
new file mode 100644
index 0000000..bdd2934
--- /dev/null
+++ b/fixtures/dedication-role-aria/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "dedication-role-aria",
+  "description": "dedication role via explicit ARIA role=\"doc-dedication\"",
+  "role": "dedication",
+  "rolesCovered": [
+    "dedication"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/dedication-role-aria/utterances.json b/fixtures/dedication-role-aria/utterances.json
new file mode 100644
index 0000000..6a7ce00
--- /dev/null
+++ b/fixtures/dedication-role-aria/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "For every keeper who lit the lamp at dusk."
+  }
+]
diff --git a/fixtures/definition-epub-type/gnd.json b/fixtures/definition-epub-type/gnd.json
new file mode 100644
index 0000000..27ad288
--- /dev/null
+++ b/fixtures/definition-epub-type/gnd.json
@@ -0,0 +1,13 @@
+{
+  "role": [
+    "glossary"
+  ],
+  "children": [
+    {
+      "role": [
+        "definition"
+      ],
+      "text": "A structure that contains an enumeration of related content items."
+    }
+  ]
+}
diff --git a/fixtures/definition-epub-type/input.html b/fixtures/definition-epub-type/input.html
new file mode 100644
index 0000000..bed6904
--- /dev/null
+++ b/fixtures/definition-epub-type/input.html
@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops">
+<head>
+<meta charset="utf-8"/>
+<title>Fixture</title>
+</head>
+<body>
+<dl epub:type="glossary">
+  <dd epub:type="glossdef">A structure that contains an enumeration of related content items.</dd>
+</dl>
+</body>
+</html>
diff --git a/fixtures/definition-epub-type/meta.json b/fixtures/definition-epub-type/meta.json
new file mode 100644
index 0000000..39c7312
--- /dev/null
+++ b/fixtures/definition-epub-type/meta.json
@@ -0,0 +1,11 @@
+{
+  "id": "definition-epub-type",
+  "description": "definition role via epub:type=\"glossdef\" on a <dd>, nested in a <dl epub:type=\"glossary\">",
+  "role": "definition",
+  "rolesCovered": [
+    "definition",
+    "glossary"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "document"
+}
diff --git a/fixtures/definition-epub-type/utterances.json b/fixtures/definition-epub-type/utterances.json
new file mode 100644
index 0000000..1919e54
--- /dev/null
+++ b/fixtures/definition-epub-type/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "A structure that contains an enumeration of related content items."
+  }
+]
diff --git a/fixtures/definition-html-native/gnd.json b/fixtures/definition-html-native/gnd.json
new file mode 100644
index 0000000..a171ac4
--- /dev/null
+++ b/fixtures/definition-html-native/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "definition"
+  ],
+  "text": "A structure that contains an enumeration of related content items."
+}
diff --git a/fixtures/definition-html-native/input.html b/fixtures/definition-html-native/input.html
new file mode 100644
index 0000000..1fffc36
--- /dev/null
+++ b/fixtures/definition-html-native/input.html
@@ -0,0 +1,3 @@
+<dl>
+  <dd>A structure that contains an enumeration of related content items.</dd>
+</dl>
diff --git a/fixtures/definition-html-native/meta.json b/fixtures/definition-html-native/meta.json
new file mode 100644
index 0000000..50fafa5
--- /dev/null
+++ b/fixtures/definition-html-native/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "definition-html-native",
+  "description": "definition role via native <dd> element, nested in a <dl> as its content model requires",
+  "role": "definition",
+  "rolesCovered": [
+    "definition"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/definition-html-native/utterances.json b/fixtures/definition-html-native/utterances.json
new file mode 100644
index 0000000..1919e54
--- /dev/null
+++ b/fixtures/definition-html-native/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "A structure that contains an enumeration of related content items."
+  }
+]
diff --git a/fixtures/definition-role-aria/gnd.json b/fixtures/definition-role-aria/gnd.json
new file mode 100644
index 0000000..a171ac4
--- /dev/null
+++ b/fixtures/definition-role-aria/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "definition"
+  ],
+  "text": "A structure that contains an enumeration of related content items."
+}
diff --git a/fixtures/definition-role-aria/input.html b/fixtures/definition-role-aria/input.html
new file mode 100644
index 0000000..be0c3cb
--- /dev/null
+++ b/fixtures/definition-role-aria/input.html
@@ -0,0 +1 @@
+<div role="definition">A structure that contains an enumeration of related content items.</div>
diff --git a/fixtures/definition-role-aria/meta.json b/fixtures/definition-role-aria/meta.json
new file mode 100644
index 0000000..5ce08f0
--- /dev/null
+++ b/fixtures/definition-role-aria/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "definition-role-aria",
+  "description": "definition role via explicit ARIA role=\"definition\"",
+  "role": "definition",
+  "rolesCovered": [
+    "definition"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/definition-role-aria/utterances.json b/fixtures/definition-role-aria/utterances.json
new file mode 100644
index 0000000..1919e54
--- /dev/null
+++ b/fixtures/definition-role-aria/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "A structure that contains an enumeration of related content items."
+  }
+]
diff --git a/fixtures/details-html-native/gnd.json b/fixtures/details-html-native/gnd.json
new file mode 100644
index 0000000..f5b5f38
--- /dev/null
+++ b/fixtures/details-html-native/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "details"
+  ],
+  "text": "Additional details the reader can expand."
+}
diff --git a/fixtures/details-html-native/input.html b/fixtures/details-html-native/input.html
new file mode 100644
index 0000000..27105bb
--- /dev/null
+++ b/fixtures/details-html-native/input.html
@@ -0,0 +1 @@
+<details>Additional details the reader can expand.</details>
diff --git a/fixtures/details-html-native/meta.json b/fixtures/details-html-native/meta.json
new file mode 100644
index 0000000..fc7d7c2
--- /dev/null
+++ b/fixtures/details-html-native/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "details-html-native",
+  "description": "details role via native <details> element",
+  "role": "details",
+  "rolesCovered": [
+    "details"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/details-html-native/utterances.json b/fixtures/details-html-native/utterances.json
new file mode 100644
index 0000000..7afa710
--- /dev/null
+++ b/fixtures/details-html-native/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "Additional details the reader can expand."
+  }
+]
diff --git a/fixtures/endnotes-epub-type/gnd.json b/fixtures/endnotes-epub-type/gnd.json
new file mode 100644
index 0000000..bbaa3b7
--- /dev/null
+++ b/fixtures/endnotes-epub-type/gnd.json
@@ -0,0 +1,42 @@
+{
+  "role": [
+    "endnotes"
+  ],
+  "children": [
+    {
+      "role": [
+        "list"
+      ],
+      "children": [
+        {
+          "role": [
+            "listItem"
+          ],
+          "children": [
+            {
+              "role": [
+                "footnote"
+              ],
+              "id": "note1",
+              "text": "See introduction for background."
+            }
+          ]
+        },
+        {
+          "role": [
+            "listItem"
+          ],
+          "children": [
+            {
+              "role": [
+                "footnote"
+              ],
+              "id": "note2",
+              "text": "See chapter three for details."
+            }
+          ]
+        }
+      ]
+    }
+  ]
+}
diff --git a/fixtures/endnotes-epub-type/input.html b/fixtures/endnotes-epub-type/input.html
new file mode 100644
index 0000000..2b98dfc
--- /dev/null
+++ b/fixtures/endnotes-epub-type/input.html
@@ -0,0 +1,16 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops">
+<head>
+<meta charset="utf-8"/>
+<title>Fixture</title>
+</head>
+<body>
+<section epub:type="endnotes">
+  <ol>
+    <li><aside id="note1" epub:type="footnote">See introduction for background.</aside></li>
+    <li><aside id="note2" epub:type="footnote">See chapter three for details.</aside></li>
+  </ol>
+</section>
+</body>
+</html>
diff --git a/fixtures/endnotes-epub-type/meta.json b/fixtures/endnotes-epub-type/meta.json
new file mode 100644
index 0000000..78854b4
--- /dev/null
+++ b/fixtures/endnotes-epub-type/meta.json
@@ -0,0 +1,13 @@
+{
+  "id": "endnotes-epub-type",
+  "description": "A collection of endnotes, via epub:type=\"endnotes\" on a <section>; each entry is an <aside epub:type=\"footnote\">",
+  "role": "endnotes",
+  "rolesCovered": [
+    "endnotes",
+    "list",
+    "listItem",
+    "footnote"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "document"
+}
diff --git a/fixtures/endnotes-epub-type/utterances.json b/fixtures/endnotes-epub-type/utterances.json
new file mode 100644
index 0000000..8ad996d
--- /dev/null
+++ b/fixtures/endnotes-epub-type/utterances.json
@@ -0,0 +1,8 @@
+[
+  {
+    "text": "See introduction for background."
+  },
+  {
+    "text": "See chapter three for details."
+  }
+]
diff --git a/fixtures/endnotes-role-aria/gnd.json b/fixtures/endnotes-role-aria/gnd.json
new file mode 100644
index 0000000..bbaa3b7
--- /dev/null
+++ b/fixtures/endnotes-role-aria/gnd.json
@@ -0,0 +1,42 @@
+{
+  "role": [
+    "endnotes"
+  ],
+  "children": [
+    {
+      "role": [
+        "list"
+      ],
+      "children": [
+        {
+          "role": [
+            "listItem"
+          ],
+          "children": [
+            {
+              "role": [
+                "footnote"
+              ],
+              "id": "note1",
+              "text": "See introduction for background."
+            }
+          ]
+        },
+        {
+          "role": [
+            "listItem"
+          ],
+          "children": [
+            {
+              "role": [
+                "footnote"
+              ],
+              "id": "note2",
+              "text": "See chapter three for details."
+            }
+          ]
+        }
+      ]
+    }
+  ]
+}
diff --git a/fixtures/endnotes-role-aria/input.html b/fixtures/endnotes-role-aria/input.html
new file mode 100644
index 0000000..53e8768
--- /dev/null
+++ b/fixtures/endnotes-role-aria/input.html
@@ -0,0 +1,6 @@
+<div role="doc-endnotes">
+  <ol>
+    <li id="note1" role="doc-footnote">See introduction for background.</li>
+    <li id="note2" role="doc-footnote">See chapter three for details.</li>
+  </ol>
+</div>
diff --git a/fixtures/endnotes-role-aria/meta.json b/fixtures/endnotes-role-aria/meta.json
new file mode 100644
index 0000000..84e40ae
--- /dev/null
+++ b/fixtures/endnotes-role-aria/meta.json
@@ -0,0 +1,13 @@
+{
+  "id": "endnotes-role-aria",
+  "description": "A collection of endnotes, via explicit ARIA role",
+  "role": "endnotes",
+  "rolesCovered": [
+    "endnotes",
+    "list",
+    "listItem",
+    "footnote"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/endnotes-role-aria/utterances.json b/fixtures/endnotes-role-aria/utterances.json
new file mode 100644
index 0000000..8ad996d
--- /dev/null
+++ b/fixtures/endnotes-role-aria/utterances.json
@@ -0,0 +1,8 @@
+[
+  {
+    "text": "See introduction for background."
+  },
+  {
+    "text": "See chapter three for details."
+  }
+]
diff --git a/fixtures/epigraph-epub-type/gnd.json b/fixtures/epigraph-epub-type/gnd.json
new file mode 100644
index 0000000..cc39a06
--- /dev/null
+++ b/fixtures/epigraph-epub-type/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "epigraph"
+  ],
+  "text": "A lighthouse is a compromise with the sea. — Anonymous"
+}
diff --git a/fixtures/epigraph-epub-type/input.html b/fixtures/epigraph-epub-type/input.html
new file mode 100644
index 0000000..0f85535
--- /dev/null
+++ b/fixtures/epigraph-epub-type/input.html
@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops">
+<head>
+<meta charset="utf-8"/>
+<title>Fixture</title>
+</head>
+<body>
+<div epub:type="epigraph">A lighthouse is a compromise with the sea. — Anonymous</div>
+</body>
+</html>
diff --git a/fixtures/epigraph-epub-type/meta.json b/fixtures/epigraph-epub-type/meta.json
new file mode 100644
index 0000000..4d18872
--- /dev/null
+++ b/fixtures/epigraph-epub-type/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "epigraph-epub-type",
+  "description": "epigraph role via epub:type=\"epigraph\"",
+  "role": "epigraph",
+  "rolesCovered": [
+    "epigraph"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "document"
+}
diff --git a/fixtures/epigraph-epub-type/utterances.json b/fixtures/epigraph-epub-type/utterances.json
new file mode 100644
index 0000000..e49b485
--- /dev/null
+++ b/fixtures/epigraph-epub-type/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "A lighthouse is a compromise with the sea. — Anonymous"
+  }
+]
diff --git a/fixtures/epigraph-role-aria/gnd.json b/fixtures/epigraph-role-aria/gnd.json
new file mode 100644
index 0000000..cc39a06
--- /dev/null
+++ b/fixtures/epigraph-role-aria/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "epigraph"
+  ],
+  "text": "A lighthouse is a compromise with the sea. — Anonymous"
+}
diff --git a/fixtures/epigraph-role-aria/input.html b/fixtures/epigraph-role-aria/input.html
new file mode 100644
index 0000000..af043b7
--- /dev/null
+++ b/fixtures/epigraph-role-aria/input.html
@@ -0,0 +1 @@
+<div role="doc-epigraph">A lighthouse is a compromise with the sea. — Anonymous</div>
diff --git a/fixtures/epigraph-role-aria/meta.json b/fixtures/epigraph-role-aria/meta.json
new file mode 100644
index 0000000..43ffda2
--- /dev/null
+++ b/fixtures/epigraph-role-aria/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "epigraph-role-aria",
+  "description": "epigraph role via explicit ARIA role=\"doc-epigraph\"",
+  "role": "epigraph",
+  "rolesCovered": [
+    "epigraph"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/epigraph-role-aria/utterances.json b/fixtures/epigraph-role-aria/utterances.json
new file mode 100644
index 0000000..e49b485
--- /dev/null
+++ b/fixtures/epigraph-role-aria/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "A lighthouse is a compromise with the sea. — Anonymous"
+  }
+]
diff --git a/fixtures/epilogue-epub-type/gnd.json b/fixtures/epilogue-epub-type/gnd.json
new file mode 100644
index 0000000..d6246aa
--- /dev/null
+++ b/fixtures/epilogue-epub-type/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "epilogue"
+  ],
+  "text": "The lamp still turns, though no one climbs the stairs anymore."
+}
diff --git a/fixtures/epilogue-epub-type/input.html b/fixtures/epilogue-epub-type/input.html
new file mode 100644
index 0000000..e72bb7a
--- /dev/null
+++ b/fixtures/epilogue-epub-type/input.html
@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops">
+<head>
+<meta charset="utf-8"/>
+<title>Fixture</title>
+</head>
+<body>
+<div epub:type="epilogue">The lamp still turns, though no one climbs the stairs anymore.</div>
+</body>
+</html>
diff --git a/fixtures/epilogue-epub-type/meta.json b/fixtures/epilogue-epub-type/meta.json
new file mode 100644
index 0000000..86d77a7
--- /dev/null
+++ b/fixtures/epilogue-epub-type/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "epilogue-epub-type",
+  "description": "epilogue role via epub:type=\"epilogue\"",
+  "role": "epilogue",
+  "rolesCovered": [
+    "epilogue"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "document"
+}
diff --git a/fixtures/epilogue-epub-type/utterances.json b/fixtures/epilogue-epub-type/utterances.json
new file mode 100644
index 0000000..bbbf7ab
--- /dev/null
+++ b/fixtures/epilogue-epub-type/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "The lamp still turns, though no one climbs the stairs anymore."
+  }
+]
diff --git a/fixtures/epilogue-role-aria/gnd.json b/fixtures/epilogue-role-aria/gnd.json
new file mode 100644
index 0000000..d6246aa
--- /dev/null
+++ b/fixtures/epilogue-role-aria/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "epilogue"
+  ],
+  "text": "The lamp still turns, though no one climbs the stairs anymore."
+}
diff --git a/fixtures/epilogue-role-aria/input.html b/fixtures/epilogue-role-aria/input.html
new file mode 100644
index 0000000..f34558b
--- /dev/null
+++ b/fixtures/epilogue-role-aria/input.html
@@ -0,0 +1 @@
+<div role="doc-epilogue">The lamp still turns, though no one climbs the stairs anymore.</div>
diff --git a/fixtures/epilogue-role-aria/meta.json b/fixtures/epilogue-role-aria/meta.json
new file mode 100644
index 0000000..51ced80
--- /dev/null
+++ b/fixtures/epilogue-role-aria/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "epilogue-role-aria",
+  "description": "epilogue role via explicit ARIA role=\"doc-epilogue\"",
+  "role": "epilogue",
+  "rolesCovered": [
+    "epilogue"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/epilogue-role-aria/utterances.json b/fixtures/epilogue-role-aria/utterances.json
new file mode 100644
index 0000000..bbbf7ab
--- /dev/null
+++ b/fixtures/epilogue-role-aria/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "The lamp still turns, though no one climbs the stairs anymore."
+  }
+]
diff --git a/fixtures/errata-epub-type/gnd.json b/fixtures/errata-epub-type/gnd.json
new file mode 100644
index 0000000..59ecbbb
--- /dev/null
+++ b/fixtures/errata-epub-type/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "errata"
+  ],
+  "text": "Page 42: 'lightouse' should read 'lighthouse'."
+}
diff --git a/fixtures/errata-epub-type/input.html b/fixtures/errata-epub-type/input.html
new file mode 100644
index 0000000..b68c130
--- /dev/null
+++ b/fixtures/errata-epub-type/input.html
@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops">
+<head>
+<meta charset="utf-8"/>
+<title>Fixture</title>
+</head>
+<body>
+<div epub:type="errata">Page 42: 'lightouse' should read 'lighthouse'.</div>
+</body>
+</html>
diff --git a/fixtures/errata-epub-type/meta.json b/fixtures/errata-epub-type/meta.json
new file mode 100644
index 0000000..1667e07
--- /dev/null
+++ b/fixtures/errata-epub-type/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "errata-epub-type",
+  "description": "errata role via epub:type=\"errata\"",
+  "role": "errata",
+  "rolesCovered": [
+    "errata"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "document"
+}
diff --git a/fixtures/errata-epub-type/utterances.json b/fixtures/errata-epub-type/utterances.json
new file mode 100644
index 0000000..c8f7308
--- /dev/null
+++ b/fixtures/errata-epub-type/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "Page 42: 'lightouse' should read 'lighthouse'."
+  }
+]
diff --git a/fixtures/errata-role-aria/gnd.json b/fixtures/errata-role-aria/gnd.json
new file mode 100644
index 0000000..59ecbbb
--- /dev/null
+++ b/fixtures/errata-role-aria/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "errata"
+  ],
+  "text": "Page 42: 'lightouse' should read 'lighthouse'."
+}
diff --git a/fixtures/errata-role-aria/input.html b/fixtures/errata-role-aria/input.html
new file mode 100644
index 0000000..0d17287
--- /dev/null
+++ b/fixtures/errata-role-aria/input.html
@@ -0,0 +1 @@
+<div role="doc-errata">Page 42: 'lightouse' should read 'lighthouse'.</div>
diff --git a/fixtures/errata-role-aria/meta.json b/fixtures/errata-role-aria/meta.json
new file mode 100644
index 0000000..f444087
--- /dev/null
+++ b/fixtures/errata-role-aria/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "errata-role-aria",
+  "description": "errata role via explicit ARIA role=\"doc-errata\"",
+  "role": "errata",
+  "rolesCovered": [
+    "errata"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/errata-role-aria/utterances.json b/fixtures/errata-role-aria/utterances.json
new file mode 100644
index 0000000..c8f7308
--- /dev/null
+++ b/fixtures/errata-role-aria/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "Page 42: 'lightouse' should read 'lighthouse'."
+  }
+]
diff --git a/fixtures/example-epub-type/gnd.json b/fixtures/example-epub-type/gnd.json
new file mode 100644
index 0000000..139a973
--- /dev/null
+++ b/fixtures/example-epub-type/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "example"
+  ],
+  "text": "For instance, a Fresnel lens focuses light into a narrow beam."
+}
diff --git a/fixtures/example-epub-type/input.html b/fixtures/example-epub-type/input.html
new file mode 100644
index 0000000..62ee80f
--- /dev/null
+++ b/fixtures/example-epub-type/input.html
@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops">
+<head>
+<meta charset="utf-8"/>
+<title>Fixture</title>
+</head>
+<body>
+<div epub:type="example">For instance, a Fresnel lens focuses light into a narrow beam.</div>
+</body>
+</html>
diff --git a/fixtures/example-epub-type/meta.json b/fixtures/example-epub-type/meta.json
new file mode 100644
index 0000000..474acdd
--- /dev/null
+++ b/fixtures/example-epub-type/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "example-epub-type",
+  "description": "example role via epub:type=\"example\"",
+  "role": "example",
+  "rolesCovered": [
+    "example"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "document"
+}
diff --git a/fixtures/example-epub-type/utterances.json b/fixtures/example-epub-type/utterances.json
new file mode 100644
index 0000000..56e0d23
--- /dev/null
+++ b/fixtures/example-epub-type/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "For instance, a Fresnel lens focuses light into a narrow beam."
+  }
+]
diff --git a/fixtures/example-role-aria/gnd.json b/fixtures/example-role-aria/gnd.json
new file mode 100644
index 0000000..139a973
--- /dev/null
+++ b/fixtures/example-role-aria/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "example"
+  ],
+  "text": "For instance, a Fresnel lens focuses light into a narrow beam."
+}
diff --git a/fixtures/example-role-aria/input.html b/fixtures/example-role-aria/input.html
new file mode 100644
index 0000000..f232ebc
--- /dev/null
+++ b/fixtures/example-role-aria/input.html
@@ -0,0 +1 @@
+<div role="doc-example">For instance, a Fresnel lens focuses light into a narrow beam.</div>
diff --git a/fixtures/example-role-aria/meta.json b/fixtures/example-role-aria/meta.json
new file mode 100644
index 0000000..785fbfb
--- /dev/null
+++ b/fixtures/example-role-aria/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "example-role-aria",
+  "description": "example role via explicit ARIA role=\"doc-example\"",
+  "role": "example",
+  "rolesCovered": [
+    "example"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/example-role-aria/utterances.json b/fixtures/example-role-aria/utterances.json
new file mode 100644
index 0000000..56e0d23
--- /dev/null
+++ b/fixtures/example-role-aria/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "For instance, a Fresnel lens focuses light into a narrow beam."
+  }
+]
diff --git a/fixtures/figure-basic-epub-type/gnd.json b/fixtures/figure-basic-epub-type/gnd.json
new file mode 100644
index 0000000..54d3788
--- /dev/null
+++ b/fixtures/figure-basic-epub-type/gnd.json
@@ -0,0 +1,14 @@
+{
+  "role": [
+    "figure"
+  ],
+  "children": [
+    {
+      "role": [
+        "image"
+      ],
+      "imgref": "chart.png",
+      "description": "A bar chart showing sales growth"
+    }
+  ]
+}
diff --git a/fixtures/figure-basic-epub-type/input.html b/fixtures/figure-basic-epub-type/input.html
new file mode 100644
index 0000000..ecd35ca
--- /dev/null
+++ b/fixtures/figure-basic-epub-type/input.html
@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops">
+<head>
+<meta charset="utf-8"/>
+<title>Fixture</title>
+</head>
+<body>
+<div epub:type="figure">
+  <img src="chart.png" alt="A bar chart showing sales growth">
+</div>
+</body>
+</html>
diff --git a/fixtures/figure-basic-epub-type/meta.json b/fixtures/figure-basic-epub-type/meta.json
new file mode 100644
index 0000000..07ff106
--- /dev/null
+++ b/fixtures/figure-basic-epub-type/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "figure-basic-epub-type",
+  "description": "A figure containing an image, with no caption, via epub:type=\"figure\"",
+  "role": "figure",
+  "rolesCovered": [
+    "figure"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/tree/main/examples/read-aloud",
+  "inputKind": "document"
+}
diff --git a/fixtures/figure-basic-epub-type/utterances.json b/fixtures/figure-basic-epub-type/utterances.json
new file mode 100644
index 0000000..2ce891d
--- /dev/null
+++ b/fixtures/figure-basic-epub-type/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "A bar chart showing sales growth"
+  }
+]
diff --git a/fixtures/figure-basic-html-native/gnd.json b/fixtures/figure-basic-html-native/gnd.json
new file mode 100644
index 0000000..54d3788
--- /dev/null
+++ b/fixtures/figure-basic-html-native/gnd.json
@@ -0,0 +1,14 @@
+{
+  "role": [
+    "figure"
+  ],
+  "children": [
+    {
+      "role": [
+        "image"
+      ],
+      "imgref": "chart.png",
+      "description": "A bar chart showing sales growth"
+    }
+  ]
+}
diff --git a/fixtures/figure-basic-html-native/input.html b/fixtures/figure-basic-html-native/input.html
new file mode 100644
index 0000000..fe8b39f
--- /dev/null
+++ b/fixtures/figure-basic-html-native/input.html
@@ -0,0 +1,3 @@
+<figure>
+  <img src="chart.png" alt="A bar chart showing sales growth">
+</figure>
diff --git a/fixtures/figure-basic-html-native/meta.json b/fixtures/figure-basic-html-native/meta.json
new file mode 100644
index 0000000..fb54766
--- /dev/null
+++ b/fixtures/figure-basic-html-native/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "figure-basic-html-native",
+  "description": "A figure containing an image, with no caption, via native <figure>",
+  "role": "figure",
+  "rolesCovered": [
+    "figure"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/tree/main/examples/read-aloud",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/figure-basic-html-native/utterances.json b/fixtures/figure-basic-html-native/utterances.json
new file mode 100644
index 0000000..2ce891d
--- /dev/null
+++ b/fixtures/figure-basic-html-native/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "A bar chart showing sales growth"
+  }
+]
diff --git a/fixtures/figure-basic-role-aria/gnd.json b/fixtures/figure-basic-role-aria/gnd.json
new file mode 100644
index 0000000..54d3788
--- /dev/null
+++ b/fixtures/figure-basic-role-aria/gnd.json
@@ -0,0 +1,14 @@
+{
+  "role": [
+    "figure"
+  ],
+  "children": [
+    {
+      "role": [
+        "image"
+      ],
+      "imgref": "chart.png",
+      "description": "A bar chart showing sales growth"
+    }
+  ]
+}
diff --git a/fixtures/figure-basic-role-aria/input.html b/fixtures/figure-basic-role-aria/input.html
new file mode 100644
index 0000000..55146f1
--- /dev/null
+++ b/fixtures/figure-basic-role-aria/input.html
@@ -0,0 +1,3 @@
+<div role="figure">
+  <img src="chart.png" alt="A bar chart showing sales growth">
+</div>
diff --git a/fixtures/figure-basic-role-aria/meta.json b/fixtures/figure-basic-role-aria/meta.json
new file mode 100644
index 0000000..a6382fd
--- /dev/null
+++ b/fixtures/figure-basic-role-aria/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "figure-basic-role-aria",
+  "description": "A figure containing an image, with no caption, via explicit role=\"figure\"",
+  "role": "figure",
+  "rolesCovered": [
+    "figure"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/tree/main/examples/read-aloud",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/figure-basic-role-aria/utterances.json b/fixtures/figure-basic-role-aria/utterances.json
new file mode 100644
index 0000000..2ce891d
--- /dev/null
+++ b/fixtures/figure-basic-role-aria/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "A bar chart showing sales growth"
+  }
+]
diff --git a/fixtures/figure-caption-html-native/gnd.json b/fixtures/figure-caption-html-native/gnd.json
new file mode 100644
index 0000000..338a00d
--- /dev/null
+++ b/fixtures/figure-caption-html-native/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "figure"
+  ],
+  "description": "ASCII Art of a cat face"
+}
diff --git a/fixtures/figure-caption-html-native/input.html b/fixtures/figure-caption-html-native/input.html
new file mode 100644
index 0000000..4962e42
--- /dev/null
+++ b/fixtures/figure-caption-html-native/input.html
@@ -0,0 +1,11 @@
+<figure aria-labelledby="cat-caption">
+  <pre>
+ /\_/\
+( o.o )
+   ^ 
+  
+  </pre>
+ <figcaption id="cat-caption">
+  ASCII Art of a cat face
+ </figcaption>
+</figure>
diff --git a/fixtures/figure-caption-html-native/meta.json b/fixtures/figure-caption-html-native/meta.json
new file mode 100644
index 0000000..16b7bf1
--- /dev/null
+++ b/fixtures/figure-caption-html-native/meta.json
@@ -0,0 +1,11 @@
+{
+  "id": "figure-caption-html-native",
+  "description": "A figure with a <pre> body and a <figcaption>, via native <figure>",
+  "role": "figure",
+  "rolesCovered": [
+    "figure",
+    "caption"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/tree/main/examples/read-aloud#images",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/figure-caption-html-native/utterances.json b/fixtures/figure-caption-html-native/utterances.json
new file mode 100644
index 0000000..c0e12c1
--- /dev/null
+++ b/fixtures/figure-caption-html-native/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "ASCII Art of a cat face"
+  }
+]
diff --git a/fixtures/figure-caption-role-aria/gnd.json b/fixtures/figure-caption-role-aria/gnd.json
new file mode 100644
index 0000000..338a00d
--- /dev/null
+++ b/fixtures/figure-caption-role-aria/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "figure"
+  ],
+  "description": "ASCII Art of a cat face"
+}
diff --git a/fixtures/figure-caption-role-aria/input.html b/fixtures/figure-caption-role-aria/input.html
new file mode 100644
index 0000000..14b18b4
--- /dev/null
+++ b/fixtures/figure-caption-role-aria/input.html
@@ -0,0 +1,11 @@
+<div role="figure" aria-labelledby="cat-caption">
+  <pre>
+ /\_/\
+( o.o )
+   ^ 
+  
+  </pre>
+ <figcaption id="cat-caption">
+  ASCII Art of a cat face
+ </figcaption>
+</div>
diff --git a/fixtures/figure-caption-role-aria/meta.json b/fixtures/figure-caption-role-aria/meta.json
new file mode 100644
index 0000000..9c4f3e2
--- /dev/null
+++ b/fixtures/figure-caption-role-aria/meta.json
@@ -0,0 +1,11 @@
+{
+  "id": "figure-caption-role-aria",
+  "description": "A figure with a <pre> body and a <figcaption>, via explicit role=\"figure\"",
+  "role": "figure",
+  "rolesCovered": [
+    "figure",
+    "caption"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/tree/main/examples/read-aloud",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/figure-caption-role-aria/utterances.json b/fixtures/figure-caption-role-aria/utterances.json
new file mode 100644
index 0000000..c0e12c1
--- /dev/null
+++ b/fixtures/figure-caption-role-aria/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "ASCII Art of a cat face"
+  }
+]
diff --git a/fixtures/figure-describedby/gnd.json b/fixtures/figure-describedby/gnd.json
new file mode 100644
index 0000000..40c9dc7
--- /dev/null
+++ b/fixtures/figure-describedby/gnd.json
@@ -0,0 +1,15 @@
+{
+  "role": [
+    "figure"
+  ],
+  "description": "Full audio description: sales grew 12% year over year, driven primarily by the Q4 holiday season.",
+  "children": [
+    {
+      "role": [
+        "image"
+      ],
+      "imgref": "chart.png",
+      "description": "Sales chart"
+    }
+  ]
+}
diff --git a/fixtures/figure-describedby/input.html b/fixtures/figure-describedby/input.html
new file mode 100644
index 0000000..8b4e1ad
--- /dev/null
+++ b/fixtures/figure-describedby/input.html
@@ -0,0 +1,4 @@
+<figure aria-describedby="chart-desc">
+  <img src="chart.png" alt="Sales chart">
+  <p id="chart-desc" hidden>Full audio description: sales grew 12% year over year, driven primarily by the Q4 holiday season.</p>
+</figure>
diff --git a/fixtures/figure-describedby/meta.json b/fixtures/figure-describedby/meta.json
new file mode 100644
index 0000000..2be600b
--- /dev/null
+++ b/fixtures/figure-describedby/meta.json
@@ -0,0 +1,11 @@
+{
+  "id": "figure-describedby",
+  "description": "A figure whose extended description comes from aria-describedby rather than a visible caption — an extension beyond the read-aloud examples doc, which only documents figcaption/aria-labelledby",
+  "role": "figure",
+  "rolesCovered": [
+    "figure",
+    "image"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/tree/main/examples/read-aloud",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/figure-describedby/utterances.json b/fixtures/figure-describedby/utterances.json
new file mode 100644
index 0000000..7f773ed
--- /dev/null
+++ b/fixtures/figure-describedby/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "Full audio description: sales grew 12% year over year, driven primarily by the Q4 holiday season."
+  }
+]
diff --git a/fixtures/footnote-epub-type/gnd.json b/fixtures/footnote-epub-type/gnd.json
new file mode 100644
index 0000000..6392f80
--- /dev/null
+++ b/fixtures/footnote-epub-type/gnd.json
@@ -0,0 +1,32 @@
+{
+  "children": [
+    {
+      "role": [
+        "paragraph"
+      ],
+      "text": {
+        "plain": "This text has a footnote.",
+        "ssml": "This text has a footnote <readium:noteref id=\"note1\" />.",
+        "language": "en"
+      },
+      "children": [
+        {
+          "role": [
+            "noteref"
+          ],
+          "id": "note1",
+          "text": "[1]",
+          "children": [
+            {
+              "role": [
+                "footnote",
+                "aside"
+              ],
+              "text": "Text of the footnote."
+            }
+          ]
+        }
+      ]
+    }
+  ]
+}
diff --git a/fixtures/footnote-epub-type/input.html b/fixtures/footnote-epub-type/input.html
new file mode 100644
index 0000000..545a012
--- /dev/null
+++ b/fixtures/footnote-epub-type/input.html
@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops">
+<head>
+<meta charset="utf-8"/>
+<title>Fixture</title>
+</head>
+<body>
+<p>This text has a footnote <a href="#note1" epub:type="noteref">[1]</a>.</p>
+<aside id="note1" epub:type="footnote">Text of the footnote.</aside>
+</body>
+</html>
diff --git a/fixtures/footnote-epub-type/meta.json b/fixtures/footnote-epub-type/meta.json
new file mode 100644
index 0000000..3731633
--- /dev/null
+++ b/fixtures/footnote-epub-type/meta.json
@@ -0,0 +1,11 @@
+{
+  "id": "footnote-epub-type",
+  "description": "A paragraph with one footnote reference and its footnote content, via epub:type",
+  "role": "footnote",
+  "rolesCovered": [
+    "footnote",
+    "noteref"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/tree/main/examples/read-aloud",
+  "inputKind": "document"
+}
diff --git a/fixtures/footnote-epub-type/utterances.json b/fixtures/footnote-epub-type/utterances.json
new file mode 100644
index 0000000..47eecb0
--- /dev/null
+++ b/fixtures/footnote-epub-type/utterances.json
@@ -0,0 +1,8 @@
+[
+  {
+    "text": "This text has a footnote."
+  },
+  {
+    "text": "Start of the footnote. Text of the footnote. End of the footnote."
+  }
+]
diff --git a/fixtures/footnote-role-aria/gnd.json b/fixtures/footnote-role-aria/gnd.json
new file mode 100644
index 0000000..6392f80
--- /dev/null
+++ b/fixtures/footnote-role-aria/gnd.json
@@ -0,0 +1,32 @@
+{
+  "children": [
+    {
+      "role": [
+        "paragraph"
+      ],
+      "text": {
+        "plain": "This text has a footnote.",
+        "ssml": "This text has a footnote <readium:noteref id=\"note1\" />.",
+        "language": "en"
+      },
+      "children": [
+        {
+          "role": [
+            "noteref"
+          ],
+          "id": "note1",
+          "text": "[1]",
+          "children": [
+            {
+              "role": [
+                "footnote",
+                "aside"
+              ],
+              "text": "Text of the footnote."
+            }
+          ]
+        }
+      ]
+    }
+  ]
+}
diff --git a/fixtures/footnote-role-aria/input.html b/fixtures/footnote-role-aria/input.html
new file mode 100644
index 0000000..3a04bd3
--- /dev/null
+++ b/fixtures/footnote-role-aria/input.html
@@ -0,0 +1,2 @@
+<p>This text has a footnote <a href="#note1" role="doc-noteref">[1]</a>.</p>
+<aside id="note1" role="doc-footnote">Text of the footnote.</aside>
diff --git a/fixtures/footnote-role-aria/meta.json b/fixtures/footnote-role-aria/meta.json
new file mode 100644
index 0000000..8175572
--- /dev/null
+++ b/fixtures/footnote-role-aria/meta.json
@@ -0,0 +1,11 @@
+{
+  "id": "footnote-role-aria",
+  "description": "A paragraph with one footnote reference and its footnote content, via explicit ARIA roles",
+  "role": "footnote",
+  "rolesCovered": [
+    "footnote",
+    "noteref"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/tree/main/examples/read-aloud",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/footnote-role-aria/utterances.json b/fixtures/footnote-role-aria/utterances.json
new file mode 100644
index 0000000..47eecb0
--- /dev/null
+++ b/fixtures/footnote-role-aria/utterances.json
@@ -0,0 +1,8 @@
+[
+  {
+    "text": "This text has a footnote."
+  },
+  {
+    "text": "Start of the footnote. Text of the footnote. End of the footnote."
+  }
+]
diff --git a/fixtures/glossary-epub-type/gnd.json b/fixtures/glossary-epub-type/gnd.json
new file mode 100644
index 0000000..e1b8e44
--- /dev/null
+++ b/fixtures/glossary-epub-type/gnd.json
@@ -0,0 +1,31 @@
+{
+  "role": [
+    "glossary"
+  ],
+  "children": [
+    {
+      "role": [
+        "term"
+      ],
+      "text": "Fresnel lens"
+    },
+    {
+      "role": [
+        "definition"
+      ],
+      "text": "A compact lens for focusing light."
+    },
+    {
+      "role": [
+        "term"
+      ],
+      "text": "Keeper"
+    },
+    {
+      "role": [
+        "definition"
+      ],
+      "text": "A person responsible for maintaining a lighthouse."
+    }
+  ]
+}
diff --git a/fixtures/glossary-epub-type/input.html b/fixtures/glossary-epub-type/input.html
new file mode 100644
index 0000000..0566368
--- /dev/null
+++ b/fixtures/glossary-epub-type/input.html
@@ -0,0 +1,16 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops">
+<head>
+<meta charset="utf-8"/>
+<title>Fixture</title>
+</head>
+<body>
+<dl epub:type="glossary">
+  <dt epub:type="glossterm">Fresnel lens</dt>
+  <dd epub:type="glossdef">A compact lens for focusing light.</dd>
+  <dt epub:type="glossterm">Keeper</dt>
+  <dd epub:type="glossdef">A person responsible for maintaining a lighthouse.</dd>
+</dl>
+</body>
+</html>
diff --git a/fixtures/glossary-epub-type/meta.json b/fixtures/glossary-epub-type/meta.json
new file mode 100644
index 0000000..306d670
--- /dev/null
+++ b/fixtures/glossary-epub-type/meta.json
@@ -0,0 +1,12 @@
+{
+  "id": "glossary-epub-type",
+  "description": "A glossary of term/definition entries via epub:type=\"glossary\" on a <dl>, with term/definition as its directly owned elements",
+  "role": "glossary",
+  "rolesCovered": [
+    "glossary",
+    "term",
+    "definition"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "document"
+}
diff --git a/fixtures/glossary-epub-type/utterances.json b/fixtures/glossary-epub-type/utterances.json
new file mode 100644
index 0000000..2d2d7c7
--- /dev/null
+++ b/fixtures/glossary-epub-type/utterances.json
@@ -0,0 +1,14 @@
+[
+  {
+    "text": "Fresnel lens"
+  },
+  {
+    "text": "A compact lens for focusing light."
+  },
+  {
+    "text": "Keeper"
+  },
+  {
+    "text": "A person responsible for maintaining a lighthouse."
+  }
+]
diff --git a/fixtures/glossary-role-aria/gnd.json b/fixtures/glossary-role-aria/gnd.json
new file mode 100644
index 0000000..e1b8e44
--- /dev/null
+++ b/fixtures/glossary-role-aria/gnd.json
@@ -0,0 +1,31 @@
+{
+  "role": [
+    "glossary"
+  ],
+  "children": [
+    {
+      "role": [
+        "term"
+      ],
+      "text": "Fresnel lens"
+    },
+    {
+      "role": [
+        "definition"
+      ],
+      "text": "A compact lens for focusing light."
+    },
+    {
+      "role": [
+        "term"
+      ],
+      "text": "Keeper"
+    },
+    {
+      "role": [
+        "definition"
+      ],
+      "text": "A person responsible for maintaining a lighthouse."
+    }
+  ]
+}
diff --git a/fixtures/glossary-role-aria/input.html b/fixtures/glossary-role-aria/input.html
new file mode 100644
index 0000000..1cdc525
--- /dev/null
+++ b/fixtures/glossary-role-aria/input.html
@@ -0,0 +1,6 @@
+<dl role="doc-glossary">
+  <dt>Fresnel lens</dt>
+  <dd>A compact lens for focusing light.</dd>
+  <dt>Keeper</dt>
+  <dd>A person responsible for maintaining a lighthouse.</dd>
+</dl>
diff --git a/fixtures/glossary-role-aria/meta.json b/fixtures/glossary-role-aria/meta.json
new file mode 100644
index 0000000..bce0105
--- /dev/null
+++ b/fixtures/glossary-role-aria/meta.json
@@ -0,0 +1,12 @@
+{
+  "id": "glossary-role-aria",
+  "description": "A glossary of term/definition entries via explicit ARIA role=\"doc-glossary\" on a <dl>, with term/definition as its directly owned elements",
+  "role": "glossary",
+  "rolesCovered": [
+    "glossary",
+    "term",
+    "definition"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/glossary-role-aria/utterances.json b/fixtures/glossary-role-aria/utterances.json
new file mode 100644
index 0000000..2d2d7c7
--- /dev/null
+++ b/fixtures/glossary-role-aria/utterances.json
@@ -0,0 +1,14 @@
+[
+  {
+    "text": "Fresnel lens"
+  },
+  {
+    "text": "A compact lens for focusing light."
+  },
+  {
+    "text": "Keeper"
+  },
+  {
+    "text": "A person responsible for maintaining a lighthouse."
+  }
+]
diff --git a/fixtures/glossref-epub-type/gnd.json b/fixtures/glossref-epub-type/gnd.json
new file mode 100644
index 0000000..1fc0c06
--- /dev/null
+++ b/fixtures/glossref-epub-type/gnd.json
@@ -0,0 +1,7 @@
+{
+  "role": [
+    "glossref"
+  ],
+  "text": "See glossary: Fresnel lens",
+  "textref": "#fresnel-lens"
+}
diff --git a/fixtures/glossref-epub-type/input.html b/fixtures/glossref-epub-type/input.html
new file mode 100644
index 0000000..3509f1d
--- /dev/null
+++ b/fixtures/glossref-epub-type/input.html
@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops">
+<head>
+<meta charset="utf-8"/>
+<title>Fixture</title>
+</head>
+<body>
+<a href="#fresnel-lens" epub:type="glossref">See glossary: Fresnel lens</a>
+</body>
+</html>
diff --git a/fixtures/glossref-epub-type/meta.json b/fixtures/glossref-epub-type/meta.json
new file mode 100644
index 0000000..d8b8bf2
--- /dev/null
+++ b/fixtures/glossref-epub-type/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "glossref-epub-type",
+  "description": "glossref role via epub:type=\"glossref\" on an <a href>",
+  "role": "glossref",
+  "rolesCovered": [
+    "glossref"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "document"
+}
diff --git a/fixtures/glossref-epub-type/utterances.json b/fixtures/glossref-epub-type/utterances.json
new file mode 100644
index 0000000..bbf831f
--- /dev/null
+++ b/fixtures/glossref-epub-type/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "See glossary: Fresnel lens"
+  }
+]
diff --git a/fixtures/glossref-role-aria/gnd.json b/fixtures/glossref-role-aria/gnd.json
new file mode 100644
index 0000000..1fc0c06
--- /dev/null
+++ b/fixtures/glossref-role-aria/gnd.json
@@ -0,0 +1,7 @@
+{
+  "role": [
+    "glossref"
+  ],
+  "text": "See glossary: Fresnel lens",
+  "textref": "#fresnel-lens"
+}
diff --git a/fixtures/glossref-role-aria/input.html b/fixtures/glossref-role-aria/input.html
new file mode 100644
index 0000000..cf0d770
--- /dev/null
+++ b/fixtures/glossref-role-aria/input.html
@@ -0,0 +1 @@
+<a href="#fresnel-lens" role="doc-glossref">See glossary: Fresnel lens</a>
diff --git a/fixtures/glossref-role-aria/meta.json b/fixtures/glossref-role-aria/meta.json
new file mode 100644
index 0000000..03addde
--- /dev/null
+++ b/fixtures/glossref-role-aria/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "glossref-role-aria",
+  "description": "glossref role via explicit ARIA role=\"doc-glossref\" on an <a href>",
+  "role": "glossref",
+  "rolesCovered": [
+    "glossref"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/glossref-role-aria/utterances.json b/fixtures/glossref-role-aria/utterances.json
new file mode 100644
index 0000000..bbf831f
--- /dev/null
+++ b/fixtures/glossref-role-aria/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "See glossary: Fresnel lens"
+  }
+]
diff --git a/fixtures/header-html-native/gnd.json b/fixtures/header-html-native/gnd.json
new file mode 100644
index 0000000..cf0d0cc
--- /dev/null
+++ b/fixtures/header-html-native/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "header"
+  ],
+  "text": "Chapter One"
+}
diff --git a/fixtures/header-html-native/input.html b/fixtures/header-html-native/input.html
new file mode 100644
index 0000000..4fbb836
--- /dev/null
+++ b/fixtures/header-html-native/input.html
@@ -0,0 +1 @@
+<header>Chapter One</header>
diff --git a/fixtures/header-html-native/meta.json b/fixtures/header-html-native/meta.json
new file mode 100644
index 0000000..328ceac
--- /dev/null
+++ b/fixtures/header-html-native/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "header-html-native",
+  "description": "header role via native <header> element",
+  "role": "header",
+  "rolesCovered": [
+    "header"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/header-html-native/utterances.json b/fixtures/header-html-native/utterances.json
new file mode 100644
index 0000000..55b5c82
--- /dev/null
+++ b/fixtures/header-html-native/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "Chapter One"
+  }
+]
diff --git a/fixtures/heading-html-native/gnd.json b/fixtures/heading-html-native/gnd.json
new file mode 100644
index 0000000..370521c
--- /dev/null
+++ b/fixtures/heading-html-native/gnd.json
@@ -0,0 +1,40 @@
+{
+  "children": [
+    {
+      "role": [
+        "heading1"
+      ],
+      "text": "Chapter One"
+    },
+    {
+      "role": [
+        "heading2"
+      ],
+      "text": "Section A"
+    },
+    {
+      "role": [
+        "heading3"
+      ],
+      "text": "Subsection i"
+    },
+    {
+      "role": [
+        "heading4"
+      ],
+      "text": "Detail heading"
+    },
+    {
+      "role": [
+        "heading5"
+      ],
+      "text": "Note heading"
+    },
+    {
+      "role": [
+        "heading6"
+      ],
+      "text": "Aside heading"
+    }
+  ]
+}
diff --git a/fixtures/heading-html-native/input.html b/fixtures/heading-html-native/input.html
new file mode 100644
index 0000000..6b22bdc
--- /dev/null
+++ b/fixtures/heading-html-native/input.html
@@ -0,0 +1,6 @@
+<h1>Chapter One</h1>
+<h2>Section A</h2>
+<h3>Subsection i</h3>
+<h4>Detail heading</h4>
+<h5>Note heading</h5>
+<h6>Aside heading</h6>
diff --git a/fixtures/heading-html-native/meta.json b/fixtures/heading-html-native/meta.json
new file mode 100644
index 0000000..dcf85d8
--- /dev/null
+++ b/fixtures/heading-html-native/meta.json
@@ -0,0 +1,15 @@
+{
+  "id": "heading-html-native",
+  "description": "heading1 through heading6 via native <h1>-<h6> elements (bundled: same pathway, repeated depth)",
+  "role": "heading",
+  "rolesCovered": [
+    "heading1",
+    "heading2",
+    "heading3",
+    "heading4",
+    "heading5",
+    "heading6"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/tree/main/examples/read-aloud",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/heading-html-native/utterances.json b/fixtures/heading-html-native/utterances.json
new file mode 100644
index 0000000..65d9331
--- /dev/null
+++ b/fixtures/heading-html-native/utterances.json
@@ -0,0 +1,20 @@
+[
+  {
+    "text": "Chapter One"
+  },
+  {
+    "text": "Section A"
+  },
+  {
+    "text": "Subsection i"
+  },
+  {
+    "text": "Detail heading"
+  },
+  {
+    "text": "Note heading"
+  },
+  {
+    "text": "Aside heading"
+  }
+]
diff --git a/fixtures/heading-role-aria/gnd.json b/fixtures/heading-role-aria/gnd.json
new file mode 100644
index 0000000..370521c
--- /dev/null
+++ b/fixtures/heading-role-aria/gnd.json
@@ -0,0 +1,40 @@
+{
+  "children": [
+    {
+      "role": [
+        "heading1"
+      ],
+      "text": "Chapter One"
+    },
+    {
+      "role": [
+        "heading2"
+      ],
+      "text": "Section A"
+    },
+    {
+      "role": [
+        "heading3"
+      ],
+      "text": "Subsection i"
+    },
+    {
+      "role": [
+        "heading4"
+      ],
+      "text": "Detail heading"
+    },
+    {
+      "role": [
+        "heading5"
+      ],
+      "text": "Note heading"
+    },
+    {
+      "role": [
+        "heading6"
+      ],
+      "text": "Aside heading"
+    }
+  ]
+}
diff --git a/fixtures/heading-role-aria/input.html b/fixtures/heading-role-aria/input.html
new file mode 100644
index 0000000..fd566d9
--- /dev/null
+++ b/fixtures/heading-role-aria/input.html
@@ -0,0 +1,6 @@
+<div role="heading" aria-level="1">Chapter One</div>
+<div role="heading" aria-level="2">Section A</div>
+<div role="heading" aria-level="3">Subsection i</div>
+<div role="heading" aria-level="4">Detail heading</div>
+<div role="heading" aria-level="5">Note heading</div>
+<div role="heading" aria-level="6">Aside heading</div>
diff --git a/fixtures/heading-role-aria/meta.json b/fixtures/heading-role-aria/meta.json
new file mode 100644
index 0000000..5b78db9
--- /dev/null
+++ b/fixtures/heading-role-aria/meta.json
@@ -0,0 +1,15 @@
+{
+  "id": "heading-role-aria",
+  "description": "heading1 through heading6 via role=\"heading\" + aria-level (bundled: same pathway, repeated depth)",
+  "role": "heading",
+  "rolesCovered": [
+    "heading1",
+    "heading2",
+    "heading3",
+    "heading4",
+    "heading5",
+    "heading6"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/tree/main/examples/read-aloud",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/heading-role-aria/utterances.json b/fixtures/heading-role-aria/utterances.json
new file mode 100644
index 0000000..65d9331
--- /dev/null
+++ b/fixtures/heading-role-aria/utterances.json
@@ -0,0 +1,20 @@
+[
+  {
+    "text": "Chapter One"
+  },
+  {
+    "text": "Section A"
+  },
+  {
+    "text": "Subsection i"
+  },
+  {
+    "text": "Detail heading"
+  },
+  {
+    "text": "Note heading"
+  },
+  {
+    "text": "Aside heading"
+  }
+]
diff --git a/fixtures/image-alt-html-native/gnd.json b/fixtures/image-alt-html-native/gnd.json
new file mode 100644
index 0000000..08475b3
--- /dev/null
+++ b/fixtures/image-alt-html-native/gnd.json
@@ -0,0 +1,7 @@
+{
+  "role": [
+    "image"
+  ],
+  "imgref": "image1.avif",
+  "description": "Alternative text using the alt attribute"
+}
diff --git a/fixtures/image-alt-html-native/input.html b/fixtures/image-alt-html-native/input.html
new file mode 100644
index 0000000..18588c4
--- /dev/null
+++ b/fixtures/image-alt-html-native/input.html
@@ -0,0 +1 @@
+<img src="image1.avif" alt="Alternative text using the alt attribute">
diff --git a/fixtures/image-alt-html-native/meta.json b/fixtures/image-alt-html-native/meta.json
new file mode 100644
index 0000000..6d6bb16
--- /dev/null
+++ b/fixtures/image-alt-html-native/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "image-alt-html-native",
+  "description": "An image with alt text via native <img alt>",
+  "role": "image",
+  "rolesCovered": [
+    "image"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/tree/main/examples/read-aloud#images",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/image-alt-html-native/utterances.json b/fixtures/image-alt-html-native/utterances.json
new file mode 100644
index 0000000..bfc6fcf
--- /dev/null
+++ b/fixtures/image-alt-html-native/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "Alternative text using the alt attribute"
+  }
+]
diff --git a/fixtures/image-decorative-empty-alt/gnd.json b/fixtures/image-decorative-empty-alt/gnd.json
new file mode 100644
index 0000000..3136698
--- /dev/null
+++ b/fixtures/image-decorative-empty-alt/gnd.json
@@ -0,0 +1,5 @@
+{
+  "role": [
+    "presentation"
+  ]
+}
diff --git a/fixtures/image-decorative-empty-alt/input.html b/fixtures/image-decorative-empty-alt/input.html
new file mode 100644
index 0000000..30a8e9d
--- /dev/null
+++ b/fixtures/image-decorative-empty-alt/input.html
@@ -0,0 +1 @@
+<img src="divider.png" alt="">
diff --git a/fixtures/image-decorative-empty-alt/meta.json b/fixtures/image-decorative-empty-alt/meta.json
new file mode 100644
index 0000000..5beab35
--- /dev/null
+++ b/fixtures/image-decorative-empty-alt/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "image-decorative-empty-alt",
+  "description": "A decorative image with empty alt, mapping to the presentation role and producing no utterance",
+  "role": "presentation",
+  "rolesCovered": [
+    "presentation"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/tree/main/examples/read-aloud",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/image-decorative-empty-alt/utterances.json b/fixtures/image-decorative-empty-alt/utterances.json
new file mode 100644
index 0000000..fe51488
--- /dev/null
+++ b/fixtures/image-decorative-empty-alt/utterances.json
@@ -0,0 +1 @@
+[]
diff --git a/fixtures/image-decorative-role-presentation/gnd.json b/fixtures/image-decorative-role-presentation/gnd.json
new file mode 100644
index 0000000..3136698
--- /dev/null
+++ b/fixtures/image-decorative-role-presentation/gnd.json
@@ -0,0 +1,5 @@
+{
+  "role": [
+    "presentation"
+  ]
+}
diff --git a/fixtures/image-decorative-role-presentation/input.html b/fixtures/image-decorative-role-presentation/input.html
new file mode 100644
index 0000000..da1e362
--- /dev/null
+++ b/fixtures/image-decorative-role-presentation/input.html
@@ -0,0 +1 @@
+<img src="divider.png" role="presentation">
diff --git a/fixtures/image-decorative-role-presentation/meta.json b/fixtures/image-decorative-role-presentation/meta.json
new file mode 100644
index 0000000..1e2d8af
--- /dev/null
+++ b/fixtures/image-decorative-role-presentation/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "image-decorative-role-presentation",
+  "description": "A decorative image marked with an explicit role=\"presentation\", producing no utterance",
+  "role": "presentation",
+  "rolesCovered": [
+    "presentation"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/tree/main/examples/read-aloud",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/image-decorative-role-presentation/utterances.json b/fixtures/image-decorative-role-presentation/utterances.json
new file mode 100644
index 0000000..fe51488
--- /dev/null
+++ b/fixtures/image-decorative-role-presentation/utterances.json
@@ -0,0 +1 @@
+[]
diff --git a/fixtures/image-role-aria/gnd.json b/fixtures/image-role-aria/gnd.json
new file mode 100644
index 0000000..b03f9f5
--- /dev/null
+++ b/fixtures/image-role-aria/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "image"
+  ],
+  "description": "Rating: 4 out of 5 stars"
+}
diff --git a/fixtures/image-role-aria/input.html b/fixtures/image-role-aria/input.html
new file mode 100644
index 0000000..be3a969
--- /dev/null
+++ b/fixtures/image-role-aria/input.html
@@ -0,0 +1,7 @@
+<span role="img" aria-label="Rating: 4 out of 5 stars">
+  <span>★</span>
+  <span>★</span>
+  <span>★</span>
+  <span>★</span>
+  <span>☆</span>
+</span>
diff --git a/fixtures/image-role-aria/meta.json b/fixtures/image-role-aria/meta.json
new file mode 100644
index 0000000..e7d4f53
--- /dev/null
+++ b/fixtures/image-role-aria/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "image-role-aria",
+  "description": "A non-<img> element acting as an image via role=\"img\" and aria-label",
+  "role": "image",
+  "rolesCovered": [
+    "image"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/tree/main/examples/read-aloud#images",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/image-role-aria/utterances.json b/fixtures/image-role-aria/utterances.json
new file mode 100644
index 0000000..8c04a58
--- /dev/null
+++ b/fixtures/image-role-aria/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "Rating: 4 out of 5 stars"
+  }
+]
diff --git a/fixtures/index-epub-type/gnd.json b/fixtures/index-epub-type/gnd.json
new file mode 100644
index 0000000..015cd04
--- /dev/null
+++ b/fixtures/index-epub-type/gnd.json
@@ -0,0 +1,28 @@
+{
+  "role": [
+    "index"
+  ],
+  "children": [
+    {
+      "role": [
+        "list"
+      ],
+      "children": [
+        {
+          "role": [
+            "listItem"
+          ],
+          "text": "Fresnel lens",
+          "textref": "chapter1.xhtml#fresnel"
+        },
+        {
+          "role": [
+            "listItem"
+          ],
+          "text": "Keepers",
+          "textref": "chapter3.xhtml#keepers"
+        }
+      ]
+    }
+  ]
+}
diff --git a/fixtures/index-epub-type/input.html b/fixtures/index-epub-type/input.html
new file mode 100644
index 0000000..9411b64
--- /dev/null
+++ b/fixtures/index-epub-type/input.html
@@ -0,0 +1,16 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops">
+<head>
+<meta charset="utf-8"/>
+<title>Fixture</title>
+</head>
+<body>
+<nav epub:type="index">
+  <ol>
+    <li><a href="chapter1.xhtml#fresnel">Fresnel lens</a></li>
+    <li><a href="chapter3.xhtml#keepers">Keepers</a></li>
+  </ol>
+</nav>
+</body>
+</html>
diff --git a/fixtures/index-epub-type/meta.json b/fixtures/index-epub-type/meta.json
new file mode 100644
index 0000000..d276ab9
--- /dev/null
+++ b/fixtures/index-epub-type/meta.json
@@ -0,0 +1,12 @@
+{
+  "id": "index-epub-type",
+  "description": "An index navigation list, containing links to key subjects and names, via epub:type",
+  "role": "index",
+  "rolesCovered": [
+    "index",
+    "list",
+    "listItem"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "document"
+}
diff --git a/fixtures/index-epub-type/utterances.json b/fixtures/index-epub-type/utterances.json
new file mode 100644
index 0000000..85bb81d
--- /dev/null
+++ b/fixtures/index-epub-type/utterances.json
@@ -0,0 +1,8 @@
+[
+  {
+    "text": "Fresnel lens"
+  },
+  {
+    "text": "Keepers"
+  }
+]
diff --git a/fixtures/index-role-aria/gnd.json b/fixtures/index-role-aria/gnd.json
new file mode 100644
index 0000000..015cd04
--- /dev/null
+++ b/fixtures/index-role-aria/gnd.json
@@ -0,0 +1,28 @@
+{
+  "role": [
+    "index"
+  ],
+  "children": [
+    {
+      "role": [
+        "list"
+      ],
+      "children": [
+        {
+          "role": [
+            "listItem"
+          ],
+          "text": "Fresnel lens",
+          "textref": "chapter1.xhtml#fresnel"
+        },
+        {
+          "role": [
+            "listItem"
+          ],
+          "text": "Keepers",
+          "textref": "chapter3.xhtml#keepers"
+        }
+      ]
+    }
+  ]
+}
diff --git a/fixtures/index-role-aria/input.html b/fixtures/index-role-aria/input.html
new file mode 100644
index 0000000..8530d89
--- /dev/null
+++ b/fixtures/index-role-aria/input.html
@@ -0,0 +1,6 @@
+<div role="doc-index">
+  <ol>
+    <li>Fresnel lens</li>
+    <li>Keepers</li>
+  </ol>
+</div>
diff --git a/fixtures/index-role-aria/meta.json b/fixtures/index-role-aria/meta.json
new file mode 100644
index 0000000..d49983e
--- /dev/null
+++ b/fixtures/index-role-aria/meta.json
@@ -0,0 +1,12 @@
+{
+  "id": "index-role-aria",
+  "description": "An index navigation list, containing links to key subjects and names, via explicit ARIA role",
+  "role": "index",
+  "rolesCovered": [
+    "index",
+    "list",
+    "listItem"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/index-role-aria/utterances.json b/fixtures/index-role-aria/utterances.json
new file mode 100644
index 0000000..85bb81d
--- /dev/null
+++ b/fixtures/index-role-aria/utterances.json
@@ -0,0 +1,8 @@
+[
+  {
+    "text": "Fresnel lens"
+  },
+  {
+    "text": "Keepers"
+  }
+]
diff --git a/fixtures/introduction-epub-type/gnd.json b/fixtures/introduction-epub-type/gnd.json
new file mode 100644
index 0000000..4eb926f
--- /dev/null
+++ b/fixtures/introduction-epub-type/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "introduction"
+  ],
+  "text": "This work explores the history of coastal lighthouses."
+}
diff --git a/fixtures/introduction-epub-type/input.html b/fixtures/introduction-epub-type/input.html
new file mode 100644
index 0000000..51000ab
--- /dev/null
+++ b/fixtures/introduction-epub-type/input.html
@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops">
+<head>
+<meta charset="utf-8"/>
+<title>Fixture</title>
+</head>
+<body>
+<div epub:type="introduction">This work explores the history of coastal lighthouses.</div>
+</body>
+</html>
diff --git a/fixtures/introduction-epub-type/meta.json b/fixtures/introduction-epub-type/meta.json
new file mode 100644
index 0000000..e34669c
--- /dev/null
+++ b/fixtures/introduction-epub-type/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "introduction-epub-type",
+  "description": "introduction role via epub:type=\"introduction\"",
+  "role": "introduction",
+  "rolesCovered": [
+    "introduction"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "document"
+}
diff --git a/fixtures/introduction-epub-type/utterances.json b/fixtures/introduction-epub-type/utterances.json
new file mode 100644
index 0000000..a4f0a1b
--- /dev/null
+++ b/fixtures/introduction-epub-type/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "This work explores the history of coastal lighthouses."
+  }
+]
diff --git a/fixtures/introduction-role-aria/gnd.json b/fixtures/introduction-role-aria/gnd.json
new file mode 100644
index 0000000..4eb926f
--- /dev/null
+++ b/fixtures/introduction-role-aria/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "introduction"
+  ],
+  "text": "This work explores the history of coastal lighthouses."
+}
diff --git a/fixtures/introduction-role-aria/input.html b/fixtures/introduction-role-aria/input.html
new file mode 100644
index 0000000..7b5c3da
--- /dev/null
+++ b/fixtures/introduction-role-aria/input.html
@@ -0,0 +1 @@
+<div role="doc-introduction">This work explores the history of coastal lighthouses.</div>
diff --git a/fixtures/introduction-role-aria/meta.json b/fixtures/introduction-role-aria/meta.json
new file mode 100644
index 0000000..b6e1b3d
--- /dev/null
+++ b/fixtures/introduction-role-aria/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "introduction-role-aria",
+  "description": "introduction role via explicit ARIA role=\"doc-introduction\"",
+  "role": "introduction",
+  "rolesCovered": [
+    "introduction"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/introduction-role-aria/utterances.json b/fixtures/introduction-role-aria/utterances.json
new file mode 100644
index 0000000..a4f0a1b
--- /dev/null
+++ b/fixtures/introduction-role-aria/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "This work explores the history of coastal lighthouses."
+  }
+]
diff --git a/fixtures/landmarks-epub-type/gnd.json b/fixtures/landmarks-epub-type/gnd.json
new file mode 100644
index 0000000..21b65c3
--- /dev/null
+++ b/fixtures/landmarks-epub-type/gnd.json
@@ -0,0 +1,35 @@
+{
+  "role": [
+    "landmarks"
+  ],
+  "children": [
+    {
+      "role": [
+        "list"
+      ],
+      "children": [
+        {
+          "role": [
+            "listItem"
+          ],
+          "text": "Cover",
+          "textref": "cover.xhtml"
+        },
+        {
+          "role": [
+            "listItem"
+          ],
+          "text": "Table of Contents",
+          "textref": "toc.xhtml"
+        },
+        {
+          "role": [
+            "listItem"
+          ],
+          "text": "Start of Content",
+          "textref": "chapter1.xhtml"
+        }
+      ]
+    }
+  ]
+}
diff --git a/fixtures/landmarks-epub-type/input.html b/fixtures/landmarks-epub-type/input.html
new file mode 100644
index 0000000..8e0a6cb
--- /dev/null
+++ b/fixtures/landmarks-epub-type/input.html
@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops">
+<head>
+<meta charset="utf-8"/>
+<title>Fixture</title>
+</head>
+<body>
+<nav epub:type="landmarks">
+  <ol>
+    <li><a href="cover.xhtml">Cover</a></li>
+    <li><a href="toc.xhtml">Table of Contents</a></li>
+    <li><a href="chapter1.xhtml">Start of Content</a></li>
+  </ol>
+</nav>
+</body>
+</html>
diff --git a/fixtures/landmarks-epub-type/meta.json b/fixtures/landmarks-epub-type/meta.json
new file mode 100644
index 0000000..e26e267
--- /dev/null
+++ b/fixtures/landmarks-epub-type/meta.json
@@ -0,0 +1,12 @@
+{
+  "id": "landmarks-epub-type",
+  "description": "A landmarks navigation list, containing links to the cover, table of contents, and start of content",
+  "role": "landmarks",
+  "rolesCovered": [
+    "landmarks",
+    "list",
+    "listItem"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "document"
+}
diff --git a/fixtures/landmarks-epub-type/utterances.json b/fixtures/landmarks-epub-type/utterances.json
new file mode 100644
index 0000000..3d06b6c
--- /dev/null
+++ b/fixtures/landmarks-epub-type/utterances.json
@@ -0,0 +1,11 @@
+[
+  {
+    "text": "Cover"
+  },
+  {
+    "text": "Table of Contents"
+  },
+  {
+    "text": "Start of Content"
+  }
+]
diff --git a/fixtures/list-html-native/gnd.json b/fixtures/list-html-native/gnd.json
new file mode 100644
index 0000000..ee08356
--- /dev/null
+++ b/fixtures/list-html-native/gnd.json
@@ -0,0 +1,25 @@
+{
+  "role": [
+    "list"
+  ],
+  "children": [
+    {
+      "role": [
+        "listItem"
+      ],
+      "text": "First item"
+    },
+    {
+      "role": [
+        "listItem"
+      ],
+      "text": "Second item"
+    },
+    {
+      "role": [
+        "listItem"
+      ],
+      "text": "Third item"
+    }
+  ]
+}
diff --git a/fixtures/list-html-native/input.html b/fixtures/list-html-native/input.html
new file mode 100644
index 0000000..424111c
--- /dev/null
+++ b/fixtures/list-html-native/input.html
@@ -0,0 +1,5 @@
+<ul>
+  <li>First item</li>
+  <li>Second item</li>
+  <li>Third item</li>
+</ul>
diff --git a/fixtures/list-html-native/meta.json b/fixtures/list-html-native/meta.json
new file mode 100644
index 0000000..e7f16e4
--- /dev/null
+++ b/fixtures/list-html-native/meta.json
@@ -0,0 +1,11 @@
+{
+  "id": "list-html-native",
+  "description": "An unordered list via native <ul>/<li> elements",
+  "role": "list",
+  "rolesCovered": [
+    "list",
+    "listItem"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/tree/main/examples/read-aloud#lists",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/list-html-native/utterances.json b/fixtures/list-html-native/utterances.json
new file mode 100644
index 0000000..8e8c458
--- /dev/null
+++ b/fixtures/list-html-native/utterances.json
@@ -0,0 +1,11 @@
+[
+  {
+    "text": "First item"
+  },
+  {
+    "text": "Second item"
+  },
+  {
+    "text": "Third item"
+  }
+]
diff --git a/fixtures/list-role-aria/gnd.json b/fixtures/list-role-aria/gnd.json
new file mode 100644
index 0000000..ee08356
--- /dev/null
+++ b/fixtures/list-role-aria/gnd.json
@@ -0,0 +1,25 @@
+{
+  "role": [
+    "list"
+  ],
+  "children": [
+    {
+      "role": [
+        "listItem"
+      ],
+      "text": "First item"
+    },
+    {
+      "role": [
+        "listItem"
+      ],
+      "text": "Second item"
+    },
+    {
+      "role": [
+        "listItem"
+      ],
+      "text": "Third item"
+    }
+  ]
+}
diff --git a/fixtures/list-role-aria/input.html b/fixtures/list-role-aria/input.html
new file mode 100644
index 0000000..b15ca42
--- /dev/null
+++ b/fixtures/list-role-aria/input.html
@@ -0,0 +1,5 @@
+<div role="list">
+  <div role="listitem">First item</div>
+  <div role="listitem">Second item</div>
+  <div role="listitem">Third item</div>
+</div>
diff --git a/fixtures/list-role-aria/meta.json b/fixtures/list-role-aria/meta.json
new file mode 100644
index 0000000..380e47b
--- /dev/null
+++ b/fixtures/list-role-aria/meta.json
@@ -0,0 +1,11 @@
+{
+  "id": "list-role-aria",
+  "description": "An unordered list via explicit role=\"list\"/\"listitem\"",
+  "role": "list",
+  "rolesCovered": [
+    "list",
+    "listItem"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/tree/main/examples/read-aloud",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/list-role-aria/utterances.json b/fixtures/list-role-aria/utterances.json
new file mode 100644
index 0000000..8e8c458
--- /dev/null
+++ b/fixtures/list-role-aria/utterances.json
@@ -0,0 +1,11 @@
+[
+  {
+    "text": "First item"
+  },
+  {
+    "text": "Second item"
+  },
+  {
+    "text": "Third item"
+  }
+]
diff --git a/fixtures/loa-epub-type/gnd.json b/fixtures/loa-epub-type/gnd.json
new file mode 100644
index 0000000..3ca91fb
--- /dev/null
+++ b/fixtures/loa-epub-type/gnd.json
@@ -0,0 +1,28 @@
+{
+  "role": [
+    "loa"
+  ],
+  "children": [
+    {
+      "role": [
+        "list"
+      ],
+      "children": [
+        {
+          "role": [
+            "listItem"
+          ],
+          "text": "Audio 1. Foghorn recording",
+          "textref": "chapter1.xhtml#audio1"
+        },
+        {
+          "role": [
+            "listItem"
+          ],
+          "text": "Audio 2. Keeper's log reading",
+          "textref": "chapter2.xhtml#audio2"
+        }
+      ]
+    }
+  ]
+}
diff --git a/fixtures/loa-epub-type/input.html b/fixtures/loa-epub-type/input.html
new file mode 100644
index 0000000..8f9061d
--- /dev/null
+++ b/fixtures/loa-epub-type/input.html
@@ -0,0 +1,16 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops">
+<head>
+<meta charset="utf-8"/>
+<title>Fixture</title>
+</head>
+<body>
+<nav epub:type="loa">
+  <ol>
+    <li><a href="chapter1.xhtml#audio1">Audio 1. Foghorn recording</a></li>
+    <li><a href="chapter2.xhtml#audio2">Audio 2. Keeper's log reading</a></li>
+  </ol>
+</nav>
+</body>
+</html>
diff --git a/fixtures/loa-epub-type/meta.json b/fixtures/loa-epub-type/meta.json
new file mode 100644
index 0000000..14dcca9
--- /dev/null
+++ b/fixtures/loa-epub-type/meta.json
@@ -0,0 +1,12 @@
+{
+  "id": "loa-epub-type",
+  "description": "A list-of-audio-clips navigation list, containing links to audio clips in the work",
+  "role": "loa",
+  "rolesCovered": [
+    "loa",
+    "list",
+    "listItem"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "document"
+}
diff --git a/fixtures/loa-epub-type/utterances.json b/fixtures/loa-epub-type/utterances.json
new file mode 100644
index 0000000..c790d26
--- /dev/null
+++ b/fixtures/loa-epub-type/utterances.json
@@ -0,0 +1,8 @@
+[
+  {
+    "text": "Audio 1. Foghorn recording"
+  },
+  {
+    "text": "Audio 2. Keeper's log reading"
+  }
+]
diff --git a/fixtures/loi-epub-type/gnd.json b/fixtures/loi-epub-type/gnd.json
new file mode 100644
index 0000000..48ca728
--- /dev/null
+++ b/fixtures/loi-epub-type/gnd.json
@@ -0,0 +1,28 @@
+{
+  "role": [
+    "loi"
+  ],
+  "children": [
+    {
+      "role": [
+        "list"
+      ],
+      "children": [
+        {
+          "role": [
+            "listItem"
+          ],
+          "text": "Figure 1. Lighthouse cross-section",
+          "textref": "chapter1.xhtml#fig1"
+        },
+        {
+          "role": [
+            "listItem"
+          ],
+          "text": "Figure 2. Fresnel lens diagram",
+          "textref": "chapter2.xhtml#fig2"
+        }
+      ]
+    }
+  ]
+}
diff --git a/fixtures/loi-epub-type/input.html b/fixtures/loi-epub-type/input.html
new file mode 100644
index 0000000..757071e
--- /dev/null
+++ b/fixtures/loi-epub-type/input.html
@@ -0,0 +1,16 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops">
+<head>
+<meta charset="utf-8"/>
+<title>Fixture</title>
+</head>
+<body>
+<nav epub:type="loi">
+  <ol>
+    <li><a href="chapter1.xhtml#fig1">Figure 1. Lighthouse cross-section</a></li>
+    <li><a href="chapter2.xhtml#fig2">Figure 2. Fresnel lens diagram</a></li>
+  </ol>
+</nav>
+</body>
+</html>
diff --git a/fixtures/loi-epub-type/meta.json b/fixtures/loi-epub-type/meta.json
new file mode 100644
index 0000000..886650b
--- /dev/null
+++ b/fixtures/loi-epub-type/meta.json
@@ -0,0 +1,12 @@
+{
+  "id": "loi-epub-type",
+  "description": "A list-of-illustrations navigation list, containing links to illustrations in the work",
+  "role": "loi",
+  "rolesCovered": [
+    "loi",
+    "list",
+    "listItem"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "document"
+}
diff --git a/fixtures/loi-epub-type/utterances.json b/fixtures/loi-epub-type/utterances.json
new file mode 100644
index 0000000..fe0ea2d
--- /dev/null
+++ b/fixtures/loi-epub-type/utterances.json
@@ -0,0 +1,8 @@
+[
+  {
+    "text": "Figure 1. Lighthouse cross-section"
+  },
+  {
+    "text": "Figure 2. Fresnel lens diagram"
+  }
+]
diff --git a/fixtures/lot-epub-type/gnd.json b/fixtures/lot-epub-type/gnd.json
new file mode 100644
index 0000000..94898db
--- /dev/null
+++ b/fixtures/lot-epub-type/gnd.json
@@ -0,0 +1,28 @@
+{
+  "role": [
+    "lot"
+  ],
+  "children": [
+    {
+      "role": [
+        "list"
+      ],
+      "children": [
+        {
+          "role": [
+            "listItem"
+          ],
+          "text": "Table 1. Lighthouse construction dates",
+          "textref": "appendix.xhtml#table1"
+        },
+        {
+          "role": [
+            "listItem"
+          ],
+          "text": "Table 2. Keeper staffing by decade",
+          "textref": "appendix.xhtml#table2"
+        }
+      ]
+    }
+  ]
+}
diff --git a/fixtures/lot-epub-type/input.html b/fixtures/lot-epub-type/input.html
new file mode 100644
index 0000000..6c0a38c
--- /dev/null
+++ b/fixtures/lot-epub-type/input.html
@@ -0,0 +1,16 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops">
+<head>
+<meta charset="utf-8"/>
+<title>Fixture</title>
+</head>
+<body>
+<nav epub:type="lot">
+  <ol>
+    <li><a href="appendix.xhtml#table1">Table 1. Lighthouse construction dates</a></li>
+    <li><a href="appendix.xhtml#table2">Table 2. Keeper staffing by decade</a></li>
+  </ol>
+</nav>
+</body>
+</html>
diff --git a/fixtures/lot-epub-type/meta.json b/fixtures/lot-epub-type/meta.json
new file mode 100644
index 0000000..f4e5468
--- /dev/null
+++ b/fixtures/lot-epub-type/meta.json
@@ -0,0 +1,12 @@
+{
+  "id": "lot-epub-type",
+  "description": "A list-of-tables navigation list, containing links to tables in the work",
+  "role": "lot",
+  "rolesCovered": [
+    "lot",
+    "list",
+    "listItem"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "document"
+}
diff --git a/fixtures/lot-epub-type/utterances.json b/fixtures/lot-epub-type/utterances.json
new file mode 100644
index 0000000..9881e95
--- /dev/null
+++ b/fixtures/lot-epub-type/utterances.json
@@ -0,0 +1,8 @@
+[
+  {
+    "text": "Table 1. Lighthouse construction dates"
+  },
+  {
+    "text": "Table 2. Keeper staffing by decade"
+  }
+]
diff --git a/fixtures/lov-epub-type/gnd.json b/fixtures/lov-epub-type/gnd.json
new file mode 100644
index 0000000..5456b84
--- /dev/null
+++ b/fixtures/lov-epub-type/gnd.json
@@ -0,0 +1,28 @@
+{
+  "role": [
+    "lov"
+  ],
+  "children": [
+    {
+      "role": [
+        "list"
+      ],
+      "children": [
+        {
+          "role": [
+            "listItem"
+          ],
+          "text": "Video 1. Lamp mechanism in motion",
+          "textref": "chapter1.xhtml#video1"
+        },
+        {
+          "role": [
+            "listItem"
+          ],
+          "text": "Video 2. Automation retrofit",
+          "textref": "chapter3.xhtml#video2"
+        }
+      ]
+    }
+  ]
+}
diff --git a/fixtures/lov-epub-type/input.html b/fixtures/lov-epub-type/input.html
new file mode 100644
index 0000000..14b4c61
--- /dev/null
+++ b/fixtures/lov-epub-type/input.html
@@ -0,0 +1,16 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops">
+<head>
+<meta charset="utf-8"/>
+<title>Fixture</title>
+</head>
+<body>
+<nav epub:type="lov">
+  <ol>
+    <li><a href="chapter1.xhtml#video1">Video 1. Lamp mechanism in motion</a></li>
+    <li><a href="chapter3.xhtml#video2">Video 2. Automation retrofit</a></li>
+  </ol>
+</nav>
+</body>
+</html>
diff --git a/fixtures/lov-epub-type/meta.json b/fixtures/lov-epub-type/meta.json
new file mode 100644
index 0000000..8adb9cc
--- /dev/null
+++ b/fixtures/lov-epub-type/meta.json
@@ -0,0 +1,12 @@
+{
+  "id": "lov-epub-type",
+  "description": "A list-of-video-clips navigation list, containing links to video clips in the work",
+  "role": "lov",
+  "rolesCovered": [
+    "lov",
+    "list",
+    "listItem"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "document"
+}
diff --git a/fixtures/lov-epub-type/utterances.json b/fixtures/lov-epub-type/utterances.json
new file mode 100644
index 0000000..be20c2b
--- /dev/null
+++ b/fixtures/lov-epub-type/utterances.json
@@ -0,0 +1,8 @@
+[
+  {
+    "text": "Video 1. Lamp mechanism in motion"
+  },
+  {
+    "text": "Video 2. Automation retrofit"
+  }
+]
diff --git a/fixtures/main-html-native/gnd.json b/fixtures/main-html-native/gnd.json
new file mode 100644
index 0000000..7302b06
--- /dev/null
+++ b/fixtures/main-html-native/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "main"
+  ],
+  "text": "The central topic of this document."
+}
diff --git a/fixtures/main-html-native/input.html b/fixtures/main-html-native/input.html
new file mode 100644
index 0000000..e4345be
--- /dev/null
+++ b/fixtures/main-html-native/input.html
@@ -0,0 +1 @@
+<main>The central topic of this document.</main>
diff --git a/fixtures/main-html-native/meta.json b/fixtures/main-html-native/meta.json
new file mode 100644
index 0000000..9b4dbf4
--- /dev/null
+++ b/fixtures/main-html-native/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "main-html-native",
+  "description": "main role via native <main> element",
+  "role": "main",
+  "rolesCovered": [
+    "main"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/main-html-native/utterances.json b/fixtures/main-html-native/utterances.json
new file mode 100644
index 0000000..19cc243
--- /dev/null
+++ b/fixtures/main-html-native/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "The central topic of this document."
+  }
+]
diff --git a/fixtures/main-role-aria/gnd.json b/fixtures/main-role-aria/gnd.json
new file mode 100644
index 0000000..7302b06
--- /dev/null
+++ b/fixtures/main-role-aria/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "main"
+  ],
+  "text": "The central topic of this document."
+}
diff --git a/fixtures/main-role-aria/input.html b/fixtures/main-role-aria/input.html
new file mode 100644
index 0000000..0725a03
--- /dev/null
+++ b/fixtures/main-role-aria/input.html
@@ -0,0 +1 @@
+<div role="main">The central topic of this document.</div>
diff --git a/fixtures/main-role-aria/meta.json b/fixtures/main-role-aria/meta.json
new file mode 100644
index 0000000..e67369b
--- /dev/null
+++ b/fixtures/main-role-aria/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "main-role-aria",
+  "description": "main role via explicit ARIA role=\"main\"",
+  "role": "main",
+  "rolesCovered": [
+    "main"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/main-role-aria/utterances.json b/fixtures/main-role-aria/utterances.json
new file mode 100644
index 0000000..19cc243
--- /dev/null
+++ b/fixtures/main-role-aria/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "The central topic of this document."
+  }
+]
diff --git a/fixtures/manifest.json b/fixtures/manifest.json
new file mode 100644
index 0000000..5f13f7c
--- /dev/null
+++ b/fixtures/manifest.json
@@ -0,0 +1,1333 @@
+[
+  {
+    "id": "abstract-epub-type",
+    "dir": "abstract-epub-type",
+    "role": "abstract",
+    "description": "abstract role via epub:type=\"abstract\"",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "abstract-role-aria",
+    "dir": "abstract-role-aria",
+    "role": "abstract",
+    "description": "abstract role via explicit ARIA role=\"doc-abstract\"",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "acknowledgments-epub-type",
+    "dir": "acknowledgments-epub-type",
+    "role": "acknowledgments",
+    "description": "acknowledgments role via epub:type=\"acknowledgments\"",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "acknowledgments-role-aria",
+    "dir": "acknowledgments-role-aria",
+    "role": "acknowledgments",
+    "description": "acknowledgments role via explicit ARIA role=\"doc-acknowledgments\"",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "afterword-epub-type",
+    "dir": "afterword-epub-type",
+    "role": "afterword",
+    "description": "afterword role via epub:type=\"afterword\"",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "afterword-role-aria",
+    "dir": "afterword-role-aria",
+    "role": "afterword",
+    "description": "afterword role via explicit ARIA role=\"doc-afterword\"",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "appendix-epub-type",
+    "dir": "appendix-epub-type",
+    "role": "appendix",
+    "description": "appendix role via epub:type=\"appendix\" on a <section>",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "appendix-role-aria",
+    "dir": "appendix-role-aria",
+    "role": "appendix",
+    "description": "appendix role via explicit ARIA role=\"doc-appendix\"",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "article-html-native",
+    "dir": "article-html-native",
+    "role": "article",
+    "description": "article role via native <article> element",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "aside-html-native",
+    "dir": "aside-html-native",
+    "role": "aside",
+    "description": "aside role via native <aside> element",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "audio-html-native",
+    "dir": "audio-html-native",
+    "role": "audio",
+    "description": "audio role via native <audio src> element, with an aria-label as the accessible description",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "backlink-epub-type",
+    "dir": "backlink-epub-type",
+    "role": "backlink",
+    "description": "backlink role via epub:type=\"backlink\" on an <a href>",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "backlink-role-aria",
+    "dir": "backlink-role-aria",
+    "role": "backlink",
+    "description": "backlink role via explicit ARIA role=\"doc-backlink\" on an <a href>",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "bibliography-epub-type",
+    "dir": "bibliography-epub-type",
+    "role": "bibliography",
+    "description": "A bibliography list of cited references, via epub:type=\"bibliography\" on a <section>",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "bibliography-role-aria",
+    "dir": "bibliography-role-aria",
+    "role": "bibliography",
+    "description": "A bibliography list of cited references, via explicit ARIA role",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "biblioref-epub-type",
+    "dir": "biblioref-epub-type",
+    "role": "biblioref",
+    "description": "biblioref role via epub:type=\"biblioref\" on an <a href>",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "biblioref-role-aria",
+    "dir": "biblioref-role-aria",
+    "role": "biblioref",
+    "description": "biblioref role via explicit ARIA role=\"doc-biblioref\" on an <a href>",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "blockquote-html-native",
+    "dir": "blockquote-html-native",
+    "role": "blockquote",
+    "description": "blockquote role via native <blockquote> element",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "body-html-native",
+    "dir": "body-html-native",
+    "role": "body",
+    "description": "body role via native <body> element",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "chapter-epub-type",
+    "dir": "chapter-epub-type",
+    "role": "chapter",
+    "description": "chapter role via epub:type=\"chapter\", containing a heading",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "chapter-role-aria",
+    "dir": "chapter-role-aria",
+    "role": "chapter",
+    "description": "chapter role via explicit ARIA role=\"doc-chapter\", containing a heading",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "colophon-epub-type",
+    "dir": "colophon-epub-type",
+    "role": "colophon",
+    "description": "colophon role via epub:type=\"colophon\"",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "colophon-role-aria",
+    "dir": "colophon-role-aria",
+    "role": "colophon",
+    "description": "colophon role via explicit ARIA role=\"doc-colophon\"",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "complementary-role-aria",
+    "dir": "complementary-role-aria",
+    "role": "complementary",
+    "description": "complementary role via explicit ARIA role=\"complementary\"",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "conclusion-epub-type",
+    "dir": "conclusion-epub-type",
+    "role": "conclusion",
+    "description": "conclusion role via epub:type=\"conclusion\"",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "conclusion-role-aria",
+    "dir": "conclusion-role-aria",
+    "role": "conclusion",
+    "description": "conclusion role via explicit ARIA role=\"doc-conclusion\"",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "cover-epub-type",
+    "dir": "cover-epub-type",
+    "role": "cover",
+    "description": "cover role via epub:type=\"cover\" on a <section> wrapping the cover image",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "cover-role-aria",
+    "dir": "cover-role-aria",
+    "role": "cover",
+    "description": "cover role via explicit ARIA role=\"doc-cover\" on an <img>",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "credit-epub-type",
+    "dir": "credit-epub-type",
+    "role": "credit",
+    "description": "credit role via epub:type=\"credit\" on a <span>",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "credit-role-aria",
+    "dir": "credit-role-aria",
+    "role": "credit",
+    "description": "credit role via explicit ARIA role=\"doc-credit\"",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "credits-epub-type",
+    "dir": "credits-epub-type",
+    "role": "credits",
+    "description": "A collection of credits, via epub:type=\"credits\"; each entry is a <span epub:type=\"credit\">",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "credits-role-aria",
+    "dir": "credits-role-aria",
+    "role": "credits",
+    "description": "A collection of credits, via explicit ARIA role",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "dedication-epub-type",
+    "dir": "dedication-epub-type",
+    "role": "dedication",
+    "description": "dedication role via epub:type=\"dedication\"",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "dedication-role-aria",
+    "dir": "dedication-role-aria",
+    "role": "dedication",
+    "description": "dedication role via explicit ARIA role=\"doc-dedication\"",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "definition-epub-type",
+    "dir": "definition-epub-type",
+    "role": "definition",
+    "description": "definition role via epub:type=\"glossdef\" on a <dd>, nested in a <dl epub:type=\"glossary\">",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "definition-html-native",
+    "dir": "definition-html-native",
+    "role": "definition",
+    "description": "definition role via native <dd> element, nested in a <dl> as its content model requires",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "definition-role-aria",
+    "dir": "definition-role-aria",
+    "role": "definition",
+    "description": "definition role via explicit ARIA role=\"definition\"",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "details-html-native",
+    "dir": "details-html-native",
+    "role": "details",
+    "description": "details role via native <details> element",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "endnotes-epub-type",
+    "dir": "endnotes-epub-type",
+    "role": "endnotes",
+    "description": "A collection of endnotes, via epub:type=\"endnotes\" on a <section>; each entry is an <aside epub:type=\"footnote\">",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "endnotes-role-aria",
+    "dir": "endnotes-role-aria",
+    "role": "endnotes",
+    "description": "A collection of endnotes, via explicit ARIA role",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "epigraph-epub-type",
+    "dir": "epigraph-epub-type",
+    "role": "epigraph",
+    "description": "epigraph role via epub:type=\"epigraph\"",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "epigraph-role-aria",
+    "dir": "epigraph-role-aria",
+    "role": "epigraph",
+    "description": "epigraph role via explicit ARIA role=\"doc-epigraph\"",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "epilogue-epub-type",
+    "dir": "epilogue-epub-type",
+    "role": "epilogue",
+    "description": "epilogue role via epub:type=\"epilogue\"",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "epilogue-role-aria",
+    "dir": "epilogue-role-aria",
+    "role": "epilogue",
+    "description": "epilogue role via explicit ARIA role=\"doc-epilogue\"",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "errata-epub-type",
+    "dir": "errata-epub-type",
+    "role": "errata",
+    "description": "errata role via epub:type=\"errata\"",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "errata-role-aria",
+    "dir": "errata-role-aria",
+    "role": "errata",
+    "description": "errata role via explicit ARIA role=\"doc-errata\"",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "example-epub-type",
+    "dir": "example-epub-type",
+    "role": "example",
+    "description": "example role via epub:type=\"example\"",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "example-role-aria",
+    "dir": "example-role-aria",
+    "role": "example",
+    "description": "example role via explicit ARIA role=\"doc-example\"",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "figure-basic-epub-type",
+    "dir": "figure-basic-epub-type",
+    "role": "figure",
+    "description": "A figure containing an image, with no caption, via epub:type=\"figure\"",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "figure-basic-html-native",
+    "dir": "figure-basic-html-native",
+    "role": "figure",
+    "description": "A figure containing an image, with no caption, via native <figure>",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "figure-basic-role-aria",
+    "dir": "figure-basic-role-aria",
+    "role": "figure",
+    "description": "A figure containing an image, with no caption, via explicit role=\"figure\"",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "figure-caption-html-native",
+    "dir": "figure-caption-html-native",
+    "role": "figure",
+    "description": "A figure with a <pre> body and a <figcaption>, via native <figure>",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "figure-caption-role-aria",
+    "dir": "figure-caption-role-aria",
+    "role": "figure",
+    "description": "A figure with a <pre> body and a <figcaption>, via explicit role=\"figure\"",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "figure-describedby",
+    "dir": "figure-describedby",
+    "role": "figure",
+    "description": "A figure whose extended description comes from aria-describedby rather than a visible caption — an extension beyond the read-aloud examples doc, which only documents figcaption/aria-labelledby",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "footnote-epub-type",
+    "dir": "footnote-epub-type",
+    "role": "footnote",
+    "description": "A paragraph with one footnote reference and its footnote content, via epub:type",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "footnote-role-aria",
+    "dir": "footnote-role-aria",
+    "role": "footnote",
+    "description": "A paragraph with one footnote reference and its footnote content, via explicit ARIA roles",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "glossary-epub-type",
+    "dir": "glossary-epub-type",
+    "role": "glossary",
+    "description": "A glossary of term/definition entries via epub:type=\"glossary\" on a <dl>, with term/definition as its directly owned elements",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "glossary-role-aria",
+    "dir": "glossary-role-aria",
+    "role": "glossary",
+    "description": "A glossary of term/definition entries via explicit ARIA role=\"doc-glossary\" on a <dl>, with term/definition as its directly owned elements",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "glossref-epub-type",
+    "dir": "glossref-epub-type",
+    "role": "glossref",
+    "description": "glossref role via epub:type=\"glossref\" on an <a href>",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "glossref-role-aria",
+    "dir": "glossref-role-aria",
+    "role": "glossref",
+    "description": "glossref role via explicit ARIA role=\"doc-glossref\" on an <a href>",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "header-html-native",
+    "dir": "header-html-native",
+    "role": "header",
+    "description": "header role via native <header> element",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "heading-html-native",
+    "dir": "heading-html-native",
+    "role": "heading",
+    "description": "heading1 through heading6 via native <h1>-<h6> elements (bundled: same pathway, repeated depth)",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "heading-role-aria",
+    "dir": "heading-role-aria",
+    "role": "heading",
+    "description": "heading1 through heading6 via role=\"heading\" + aria-level (bundled: same pathway, repeated depth)",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "image-alt-html-native",
+    "dir": "image-alt-html-native",
+    "role": "image",
+    "description": "An image with alt text via native <img alt>",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "image-decorative-empty-alt",
+    "dir": "image-decorative-empty-alt",
+    "role": "presentation",
+    "description": "A decorative image with empty alt, mapping to the presentation role and producing no utterance",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "image-decorative-role-presentation",
+    "dir": "image-decorative-role-presentation",
+    "role": "presentation",
+    "description": "A decorative image marked with an explicit role=\"presentation\", producing no utterance",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "image-role-aria",
+    "dir": "image-role-aria",
+    "role": "image",
+    "description": "A non-<img> element acting as an image via role=\"img\" and aria-label",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "index-epub-type",
+    "dir": "index-epub-type",
+    "role": "index",
+    "description": "An index navigation list, containing links to key subjects and names, via epub:type",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "index-role-aria",
+    "dir": "index-role-aria",
+    "role": "index",
+    "description": "An index navigation list, containing links to key subjects and names, via explicit ARIA role",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "introduction-epub-type",
+    "dir": "introduction-epub-type",
+    "role": "introduction",
+    "description": "introduction role via epub:type=\"introduction\"",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "introduction-role-aria",
+    "dir": "introduction-role-aria",
+    "role": "introduction",
+    "description": "introduction role via explicit ARIA role=\"doc-introduction\"",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "landmarks-epub-type",
+    "dir": "landmarks-epub-type",
+    "role": "landmarks",
+    "description": "A landmarks navigation list, containing links to the cover, table of contents, and start of content",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "list-html-native",
+    "dir": "list-html-native",
+    "role": "list",
+    "description": "An unordered list via native <ul>/<li> elements",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "list-role-aria",
+    "dir": "list-role-aria",
+    "role": "list",
+    "description": "An unordered list via explicit role=\"list\"/\"listitem\"",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "loa-epub-type",
+    "dir": "loa-epub-type",
+    "role": "loa",
+    "description": "A list-of-audio-clips navigation list, containing links to audio clips in the work",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "loi-epub-type",
+    "dir": "loi-epub-type",
+    "role": "loi",
+    "description": "A list-of-illustrations navigation list, containing links to illustrations in the work",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "lot-epub-type",
+    "dir": "lot-epub-type",
+    "role": "lot",
+    "description": "A list-of-tables navigation list, containing links to tables in the work",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "lov-epub-type",
+    "dir": "lov-epub-type",
+    "role": "lov",
+    "description": "A list-of-video-clips navigation list, containing links to video clips in the work",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "main-html-native",
+    "dir": "main-html-native",
+    "role": "main",
+    "description": "main role via native <main> element",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "main-role-aria",
+    "dir": "main-role-aria",
+    "role": "main",
+    "description": "main role via explicit ARIA role=\"main\"",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "math-html-native",
+    "dir": "math-html-native",
+    "role": "math",
+    "description": "math role via native MathML <math> markup, with a spoken-form description for read-aloud",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "math-role-aria",
+    "dir": "math-role-aria",
+    "role": "math",
+    "description": "math role via explicit ARIA role=\"math\" on a rendered formula, with an aria-label carrying the spoken form for read-aloud",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "navigation-html-native",
+    "dir": "navigation-html-native",
+    "role": "navigation",
+    "description": "navigation role via native <nav> element",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "navigation-role-aria",
+    "dir": "navigation-role-aria",
+    "role": "navigation",
+    "description": "navigation role via explicit ARIA role=\"navigation\"",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "notice-epub-type",
+    "dir": "notice-epub-type",
+    "role": "notice",
+    "description": "notice role via epub:type=\"notice\"",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "notice-role-aria",
+    "dir": "notice-role-aria",
+    "role": "notice",
+    "description": "notice role via explicit ARIA role=\"doc-notice\"",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "pagebreak-epub-type",
+    "dir": "pagebreak-epub-type",
+    "role": "pagebreak",
+    "description": "A standalone pagebreak between two paragraphs, via epub:type=\"pagebreak\"",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "pagebreak-role-aria",
+    "dir": "pagebreak-role-aria",
+    "role": "pagebreak",
+    "description": "A standalone pagebreak between two paragraphs, via role=\"doc-pagebreak\"",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "pagelist-epub-type",
+    "dir": "pagelist-epub-type",
+    "role": "pagelist",
+    "description": "A page-list navigation list, containing links to pagebreaks, via epub:type",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "pagelist-role-aria",
+    "dir": "pagelist-role-aria",
+    "role": "pagelist",
+    "description": "A page-list navigation list, containing links to pagebreaks, via explicit ARIA role",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "paragraph-basic",
+    "dir": "paragraph-basic",
+    "role": "paragraph",
+    "description": "A single paragraph, the only encoding pathway for this role",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "paragraph-multilingual-ssml-lang",
+    "dir": "paragraph-multilingual-ssml-lang",
+    "role": "paragraph",
+    "description": "A paragraph with an inline foreign-language phrase, represented via SSML",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "paragraph-multilingual-text-children",
+    "dir": "paragraph-multilingual-text-children",
+    "role": "paragraph",
+    "description": "A paragraph with an inline foreign-language phrase, represented as separate text children per language",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "part-epub-type",
+    "dir": "part-epub-type",
+    "role": "part",
+    "description": "part role via epub:type=\"part\", containing a heading",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "part-role-aria",
+    "dir": "part-role-aria",
+    "role": "part",
+    "description": "part role via explicit ARIA role=\"doc-part\", containing a heading",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "preface-epub-type",
+    "dir": "preface-epub-type",
+    "role": "preface",
+    "description": "preface role via epub:type=\"preface\"",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "preface-role-aria",
+    "dir": "preface-role-aria",
+    "role": "preface",
+    "description": "preface role via explicit ARIA role=\"doc-preface\"",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "preformatted-html-native",
+    "dir": "preformatted-html-native",
+    "role": "preformatted",
+    "description": "preformatted role via native <pre> element",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "presentation-role-aria",
+    "dir": "presentation-role-aria",
+    "role": "presentation",
+    "description": "presentation role via explicit ARIA role=\"presentation\"",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "prologue-epub-type",
+    "dir": "prologue-epub-type",
+    "role": "prologue",
+    "description": "prologue role via epub:type=\"prologue\"",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "prologue-role-aria",
+    "dir": "prologue-role-aria",
+    "role": "prologue",
+    "description": "prologue role via explicit ARIA role=\"doc-prologue\"",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "pullquote-epub-type",
+    "dir": "pullquote-epub-type",
+    "role": "pullquote",
+    "description": "pullquote role via epub:type=\"pullquote\" on an <aside>",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "pullquote-role-aria",
+    "dir": "pullquote-role-aria",
+    "role": "pullquote",
+    "description": "pullquote role via explicit ARIA role=\"doc-pullquote\"",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "qna-epub-type",
+    "dir": "qna-epub-type",
+    "role": "qna",
+    "description": "qna role via epub:type=\"qna\" on a <section>",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "qna-role-aria",
+    "dir": "qna-role-aria",
+    "role": "qna",
+    "description": "qna role via explicit ARIA role=\"doc-qna\"",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "region-role-aria",
+    "dir": "region-role-aria",
+    "role": "region",
+    "description": "region role via explicit ARIA role=\"region\"",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "separator-html-native",
+    "dir": "separator-html-native",
+    "role": "separator",
+    "description": "separator role via native <hr> element; a purely visual divider with no read-aloud content",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "separator-role-aria",
+    "dir": "separator-role-aria",
+    "role": "separator",
+    "description": "separator role via explicit ARIA role=\"separator\"; a purely visual divider with no read-aloud content",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "subtitle-epub-type",
+    "dir": "subtitle-epub-type",
+    "role": "subtitle",
+    "description": "subtitle role via epub:type=\"subtitle\"",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "subtitle-role-aria",
+    "dir": "subtitle-role-aria",
+    "role": "subtitle",
+    "description": "subtitle role via explicit ARIA role=\"doc-subtitle\"",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "summary-html-native",
+    "dir": "summary-html-native",
+    "role": "summary",
+    "description": "summary role via native <summary> element",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "table-html-native",
+    "dir": "table-html-native",
+    "role": "table",
+    "description": "A table with a header row, via native <table>/<tr>/<th>/<td>",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "table-role-aria",
+    "dir": "table-role-aria",
+    "role": "table",
+    "description": "A table with a header row, via explicit ARIA table/row/columnheader/cell roles",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "term-epub-type",
+    "dir": "term-epub-type",
+    "role": "term",
+    "description": "term role via epub:type=\"glossterm\" on a <dt>, nested in a <dl epub:type=\"glossary\">",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "term-html-native",
+    "dir": "term-html-native",
+    "role": "term",
+    "description": "term role via native <dfn> element",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "term-role-aria",
+    "dir": "term-role-aria",
+    "role": "term",
+    "description": "term role via explicit ARIA role=\"term\"",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "tip-epub-type",
+    "dir": "tip-epub-type",
+    "role": "tip",
+    "description": "tip role via epub:type=\"tip\" on an <aside>",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "tip-role-aria",
+    "dir": "tip-role-aria",
+    "role": "tip",
+    "description": "tip role via explicit ARIA role=\"doc-tip\"",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "toc-epub-type",
+    "dir": "toc-epub-type",
+    "role": "toc",
+    "description": "A table-of-contents navigation list, containing links to sectional headings, via epub:type",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "toc-role-aria",
+    "dir": "toc-role-aria",
+    "role": "toc",
+    "description": "A table-of-contents navigation list, containing links to sectional headings, via explicit ARIA role",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "video-html-native",
+    "dir": "video-html-native",
+    "role": "video",
+    "description": "video role via native <video src> element, with an aria-label as the accessible description",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  }
+]
diff --git a/fixtures/math-html-native/gnd.json b/fixtures/math-html-native/gnd.json
new file mode 100644
index 0000000..2054d35
--- /dev/null
+++ b/fixtures/math-html-native/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "math"
+  ],
+  "description": "x squared plus y squared equals z squared"
+}
diff --git a/fixtures/math-html-native/input.html b/fixtures/math-html-native/input.html
new file mode 100644
index 0000000..8ce201f
--- /dev/null
+++ b/fixtures/math-html-native/input.html
@@ -0,0 +1,7 @@
+<math>
+  <msup><mi>x</mi><mn>2</mn></msup>
+  <mo>+</mo>
+  <msup><mi>y</mi><mn>2</mn></msup>
+  <mo>=</mo>
+  <msup><mi>z</mi><mn>2</mn></msup>
+</math>
diff --git a/fixtures/math-html-native/meta.json b/fixtures/math-html-native/meta.json
new file mode 100644
index 0000000..9a64687
--- /dev/null
+++ b/fixtures/math-html-native/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "math-html-native",
+  "description": "math role via native MathML <math> markup, with a spoken-form description for read-aloud",
+  "role": "math",
+  "rolesCovered": [
+    "math"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/math-html-native/utterances.json b/fixtures/math-html-native/utterances.json
new file mode 100644
index 0000000..2e5d8a9
--- /dev/null
+++ b/fixtures/math-html-native/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "x squared plus y squared equals z squared"
+  }
+]
diff --git a/fixtures/math-role-aria/gnd.json b/fixtures/math-role-aria/gnd.json
new file mode 100644
index 0000000..2054d35
--- /dev/null
+++ b/fixtures/math-role-aria/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "math"
+  ],
+  "description": "x squared plus y squared equals z squared"
+}
diff --git a/fixtures/math-role-aria/input.html b/fixtures/math-role-aria/input.html
new file mode 100644
index 0000000..59f0e3c
--- /dev/null
+++ b/fixtures/math-role-aria/input.html
@@ -0,0 +1 @@
+<span role="math" aria-label="x squared plus y squared equals z squared">x² + y² = z²</span>
diff --git a/fixtures/math-role-aria/meta.json b/fixtures/math-role-aria/meta.json
new file mode 100644
index 0000000..f673a67
--- /dev/null
+++ b/fixtures/math-role-aria/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "math-role-aria",
+  "description": "math role via explicit ARIA role=\"math\" on a rendered formula, with an aria-label carrying the spoken form for read-aloud",
+  "role": "math",
+  "rolesCovered": [
+    "math"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/math-role-aria/utterances.json b/fixtures/math-role-aria/utterances.json
new file mode 100644
index 0000000..2e5d8a9
--- /dev/null
+++ b/fixtures/math-role-aria/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "x squared plus y squared equals z squared"
+  }
+]
diff --git a/fixtures/navigation-html-native/gnd.json b/fixtures/navigation-html-native/gnd.json
new file mode 100644
index 0000000..06945a4
--- /dev/null
+++ b/fixtures/navigation-html-native/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "navigation"
+  ],
+  "text": "Link to the next chapter."
+}
diff --git a/fixtures/navigation-html-native/input.html b/fixtures/navigation-html-native/input.html
new file mode 100644
index 0000000..7717335
--- /dev/null
+++ b/fixtures/navigation-html-native/input.html
@@ -0,0 +1 @@
+<nav>Link to the next chapter.</nav>
diff --git a/fixtures/navigation-html-native/meta.json b/fixtures/navigation-html-native/meta.json
new file mode 100644
index 0000000..08b5d80
--- /dev/null
+++ b/fixtures/navigation-html-native/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "navigation-html-native",
+  "description": "navigation role via native <nav> element",
+  "role": "navigation",
+  "rolesCovered": [
+    "navigation"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/navigation-html-native/utterances.json b/fixtures/navigation-html-native/utterances.json
new file mode 100644
index 0000000..5cb5820
--- /dev/null
+++ b/fixtures/navigation-html-native/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "Link to the next chapter."
+  }
+]
diff --git a/fixtures/navigation-role-aria/gnd.json b/fixtures/navigation-role-aria/gnd.json
new file mode 100644
index 0000000..06945a4
--- /dev/null
+++ b/fixtures/navigation-role-aria/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "navigation"
+  ],
+  "text": "Link to the next chapter."
+}
diff --git a/fixtures/navigation-role-aria/input.html b/fixtures/navigation-role-aria/input.html
new file mode 100644
index 0000000..617f494
--- /dev/null
+++ b/fixtures/navigation-role-aria/input.html
@@ -0,0 +1 @@
+<div role="navigation">Link to the next chapter.</div>
diff --git a/fixtures/navigation-role-aria/meta.json b/fixtures/navigation-role-aria/meta.json
new file mode 100644
index 0000000..b713245
--- /dev/null
+++ b/fixtures/navigation-role-aria/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "navigation-role-aria",
+  "description": "navigation role via explicit ARIA role=\"navigation\"",
+  "role": "navigation",
+  "rolesCovered": [
+    "navigation"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/navigation-role-aria/utterances.json b/fixtures/navigation-role-aria/utterances.json
new file mode 100644
index 0000000..5cb5820
--- /dev/null
+++ b/fixtures/navigation-role-aria/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "Link to the next chapter."
+  }
+]
diff --git a/fixtures/notice-epub-type/gnd.json b/fixtures/notice-epub-type/gnd.json
new file mode 100644
index 0000000..1a36593
--- /dev/null
+++ b/fixtures/notice-epub-type/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "notice"
+  ],
+  "text": "Caution: the tower stairs are uneven."
+}
diff --git a/fixtures/notice-epub-type/input.html b/fixtures/notice-epub-type/input.html
new file mode 100644
index 0000000..11dd8ea
--- /dev/null
+++ b/fixtures/notice-epub-type/input.html
@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops">
+<head>
+<meta charset="utf-8"/>
+<title>Fixture</title>
+</head>
+<body>
+<div epub:type="notice">Caution: the tower stairs are uneven.</div>
+</body>
+</html>
diff --git a/fixtures/notice-epub-type/meta.json b/fixtures/notice-epub-type/meta.json
new file mode 100644
index 0000000..acd14fe
--- /dev/null
+++ b/fixtures/notice-epub-type/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "notice-epub-type",
+  "description": "notice role via epub:type=\"notice\"",
+  "role": "notice",
+  "rolesCovered": [
+    "notice"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "document"
+}
diff --git a/fixtures/notice-epub-type/utterances.json b/fixtures/notice-epub-type/utterances.json
new file mode 100644
index 0000000..b3f97c3
--- /dev/null
+++ b/fixtures/notice-epub-type/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "Caution: the tower stairs are uneven."
+  }
+]
diff --git a/fixtures/notice-role-aria/gnd.json b/fixtures/notice-role-aria/gnd.json
new file mode 100644
index 0000000..1a36593
--- /dev/null
+++ b/fixtures/notice-role-aria/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "notice"
+  ],
+  "text": "Caution: the tower stairs are uneven."
+}
diff --git a/fixtures/notice-role-aria/input.html b/fixtures/notice-role-aria/input.html
new file mode 100644
index 0000000..57e4f71
--- /dev/null
+++ b/fixtures/notice-role-aria/input.html
@@ -0,0 +1 @@
+<div role="doc-notice">Caution: the tower stairs are uneven.</div>
diff --git a/fixtures/notice-role-aria/meta.json b/fixtures/notice-role-aria/meta.json
new file mode 100644
index 0000000..20bb968
--- /dev/null
+++ b/fixtures/notice-role-aria/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "notice-role-aria",
+  "description": "notice role via explicit ARIA role=\"doc-notice\"",
+  "role": "notice",
+  "rolesCovered": [
+    "notice"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/notice-role-aria/utterances.json b/fixtures/notice-role-aria/utterances.json
new file mode 100644
index 0000000..b3f97c3
--- /dev/null
+++ b/fixtures/notice-role-aria/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "Caution: the tower stairs are uneven."
+  }
+]
diff --git a/fixtures/pagebreak-epub-type/gnd.json b/fixtures/pagebreak-epub-type/gnd.json
new file mode 100644
index 0000000..3397c22
--- /dev/null
+++ b/fixtures/pagebreak-epub-type/gnd.json
@@ -0,0 +1,22 @@
+{
+  "children": [
+    {
+      "role": [
+        "paragraph"
+      ],
+      "text": "End of the previous page."
+    },
+    {
+      "role": [
+        "pagebreak"
+      ],
+      "text": "5"
+    },
+    {
+      "role": [
+        "paragraph"
+      ],
+      "text": "Start of the next page."
+    }
+  ]
+}
diff --git a/fixtures/pagebreak-epub-type/input.html b/fixtures/pagebreak-epub-type/input.html
new file mode 100644
index 0000000..bf43c2c
--- /dev/null
+++ b/fixtures/pagebreak-epub-type/input.html
@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops">
+<head>
+<meta charset="utf-8"/>
+<title>Fixture</title>
+</head>
+<body>
+<p>End of the previous page.</p>
+<span epub:type="pagebreak" title="5"></span>
+<p>Start of the next page.</p>
+</body>
+</html>
diff --git a/fixtures/pagebreak-epub-type/meta.json b/fixtures/pagebreak-epub-type/meta.json
new file mode 100644
index 0000000..7b2a104
--- /dev/null
+++ b/fixtures/pagebreak-epub-type/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "pagebreak-epub-type",
+  "description": "A standalone pagebreak between two paragraphs, via epub:type=\"pagebreak\"",
+  "role": "pagebreak",
+  "rolesCovered": [
+    "pagebreak"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/tree/main/examples/read-aloud",
+  "inputKind": "document"
+}
diff --git a/fixtures/pagebreak-epub-type/utterances.json b/fixtures/pagebreak-epub-type/utterances.json
new file mode 100644
index 0000000..328b01a
--- /dev/null
+++ b/fixtures/pagebreak-epub-type/utterances.json
@@ -0,0 +1,11 @@
+[
+  {
+    "text": "End of the previous page."
+  },
+  {
+    "text": "Pagebreak. Page: 5."
+  },
+  {
+    "text": "Start of the next page."
+  }
+]
diff --git a/fixtures/pagebreak-role-aria/gnd.json b/fixtures/pagebreak-role-aria/gnd.json
new file mode 100644
index 0000000..3397c22
--- /dev/null
+++ b/fixtures/pagebreak-role-aria/gnd.json
@@ -0,0 +1,22 @@
+{
+  "children": [
+    {
+      "role": [
+        "paragraph"
+      ],
+      "text": "End of the previous page."
+    },
+    {
+      "role": [
+        "pagebreak"
+      ],
+      "text": "5"
+    },
+    {
+      "role": [
+        "paragraph"
+      ],
+      "text": "Start of the next page."
+    }
+  ]
+}
diff --git a/fixtures/pagebreak-role-aria/input.html b/fixtures/pagebreak-role-aria/input.html
new file mode 100644
index 0000000..3152fb0
--- /dev/null
+++ b/fixtures/pagebreak-role-aria/input.html
@@ -0,0 +1,3 @@
+<p>End of the previous page.</p>
+<span role="doc-pagebreak" title="5"></span>
+<p>Start of the next page.</p>
diff --git a/fixtures/pagebreak-role-aria/meta.json b/fixtures/pagebreak-role-aria/meta.json
new file mode 100644
index 0000000..01c1759
--- /dev/null
+++ b/fixtures/pagebreak-role-aria/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "pagebreak-role-aria",
+  "description": "A standalone pagebreak between two paragraphs, via role=\"doc-pagebreak\"",
+  "role": "pagebreak",
+  "rolesCovered": [
+    "pagebreak"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/tree/main/examples/read-aloud",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/pagebreak-role-aria/utterances.json b/fixtures/pagebreak-role-aria/utterances.json
new file mode 100644
index 0000000..328b01a
--- /dev/null
+++ b/fixtures/pagebreak-role-aria/utterances.json
@@ -0,0 +1,11 @@
+[
+  {
+    "text": "End of the previous page."
+  },
+  {
+    "text": "Pagebreak. Page: 5."
+  },
+  {
+    "text": "Start of the next page."
+  }
+]
diff --git a/fixtures/pagelist-epub-type/gnd.json b/fixtures/pagelist-epub-type/gnd.json
new file mode 100644
index 0000000..bcc4f55
--- /dev/null
+++ b/fixtures/pagelist-epub-type/gnd.json
@@ -0,0 +1,35 @@
+{
+  "role": [
+    "pagelist"
+  ],
+  "children": [
+    {
+      "role": [
+        "list"
+      ],
+      "children": [
+        {
+          "role": [
+            "listItem"
+          ],
+          "text": "Page 1",
+          "textref": "#pg1"
+        },
+        {
+          "role": [
+            "listItem"
+          ],
+          "text": "Page 2",
+          "textref": "#pg2"
+        },
+        {
+          "role": [
+            "listItem"
+          ],
+          "text": "Page 3",
+          "textref": "#pg3"
+        }
+      ]
+    }
+  ]
+}
diff --git a/fixtures/pagelist-epub-type/input.html b/fixtures/pagelist-epub-type/input.html
new file mode 100644
index 0000000..66f86d4
--- /dev/null
+++ b/fixtures/pagelist-epub-type/input.html
@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops">
+<head>
+<meta charset="utf-8"/>
+<title>Fixture</title>
+</head>
+<body>
+<nav epub:type="page-list">
+  <ol>
+    <li><a href="#pg1">Page 1</a></li>
+    <li><a href="#pg2">Page 2</a></li>
+    <li><a href="#pg3">Page 3</a></li>
+  </ol>
+</nav>
+</body>
+</html>
diff --git a/fixtures/pagelist-epub-type/meta.json b/fixtures/pagelist-epub-type/meta.json
new file mode 100644
index 0000000..416efde
--- /dev/null
+++ b/fixtures/pagelist-epub-type/meta.json
@@ -0,0 +1,12 @@
+{
+  "id": "pagelist-epub-type",
+  "description": "A page-list navigation list, containing links to pagebreaks, via epub:type",
+  "role": "pagelist",
+  "rolesCovered": [
+    "pagelist",
+    "list",
+    "listItem"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "document"
+}
diff --git a/fixtures/pagelist-epub-type/utterances.json b/fixtures/pagelist-epub-type/utterances.json
new file mode 100644
index 0000000..2702bc1
--- /dev/null
+++ b/fixtures/pagelist-epub-type/utterances.json
@@ -0,0 +1,11 @@
+[
+  {
+    "text": "Page 1"
+  },
+  {
+    "text": "Page 2"
+  },
+  {
+    "text": "Page 3"
+  }
+]
diff --git a/fixtures/pagelist-role-aria/gnd.json b/fixtures/pagelist-role-aria/gnd.json
new file mode 100644
index 0000000..bcc4f55
--- /dev/null
+++ b/fixtures/pagelist-role-aria/gnd.json
@@ -0,0 +1,35 @@
+{
+  "role": [
+    "pagelist"
+  ],
+  "children": [
+    {
+      "role": [
+        "list"
+      ],
+      "children": [
+        {
+          "role": [
+            "listItem"
+          ],
+          "text": "Page 1",
+          "textref": "#pg1"
+        },
+        {
+          "role": [
+            "listItem"
+          ],
+          "text": "Page 2",
+          "textref": "#pg2"
+        },
+        {
+          "role": [
+            "listItem"
+          ],
+          "text": "Page 3",
+          "textref": "#pg3"
+        }
+      ]
+    }
+  ]
+}
diff --git a/fixtures/pagelist-role-aria/input.html b/fixtures/pagelist-role-aria/input.html
new file mode 100644
index 0000000..77a9830
--- /dev/null
+++ b/fixtures/pagelist-role-aria/input.html
@@ -0,0 +1,7 @@
+<nav role="doc-pagelist">
+  <ol>
+    <li><a href="#pg1">Page 1</a></li>
+    <li><a href="#pg2">Page 2</a></li>
+    <li><a href="#pg3">Page 3</a></li>
+  </ol>
+</nav>
diff --git a/fixtures/pagelist-role-aria/meta.json b/fixtures/pagelist-role-aria/meta.json
new file mode 100644
index 0000000..81c0ee5
--- /dev/null
+++ b/fixtures/pagelist-role-aria/meta.json
@@ -0,0 +1,12 @@
+{
+  "id": "pagelist-role-aria",
+  "description": "A page-list navigation list, containing links to pagebreaks, via explicit ARIA role",
+  "role": "pagelist",
+  "rolesCovered": [
+    "pagelist",
+    "list",
+    "listItem"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/pagelist-role-aria/utterances.json b/fixtures/pagelist-role-aria/utterances.json
new file mode 100644
index 0000000..2702bc1
--- /dev/null
+++ b/fixtures/pagelist-role-aria/utterances.json
@@ -0,0 +1,11 @@
+[
+  {
+    "text": "Page 1"
+  },
+  {
+    "text": "Page 2"
+  },
+  {
+    "text": "Page 3"
+  }
+]
diff --git a/fixtures/paragraph-basic/gnd.json b/fixtures/paragraph-basic/gnd.json
new file mode 100644
index 0000000..a9d47f9
--- /dev/null
+++ b/fixtures/paragraph-basic/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "paragraph"
+  ],
+  "text": "It is a truth universally acknowledged, that a single man in possession of a good fortune, must be in want of a wife."
+}
diff --git a/fixtures/paragraph-basic/input.html b/fixtures/paragraph-basic/input.html
new file mode 100644
index 0000000..3a1e36e
--- /dev/null
+++ b/fixtures/paragraph-basic/input.html
@@ -0,0 +1 @@
+<p>It is a truth universally acknowledged, that a single man in possession of a good fortune, must be in want of a wife.</p>
diff --git a/fixtures/paragraph-basic/meta.json b/fixtures/paragraph-basic/meta.json
new file mode 100644
index 0000000..9dc55ae
--- /dev/null
+++ b/fixtures/paragraph-basic/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "paragraph-basic",
+  "description": "A single paragraph, the only encoding pathway for this role",
+  "role": "paragraph",
+  "rolesCovered": [
+    "paragraph"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/tree/main/examples/read-aloud#paragraphs",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/paragraph-basic/utterances.json b/fixtures/paragraph-basic/utterances.json
new file mode 100644
index 0000000..389ed63
--- /dev/null
+++ b/fixtures/paragraph-basic/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "It is a truth universally acknowledged, that a single man in possession of a good fortune, must be in want of a wife."
+  }
+]
diff --git a/fixtures/paragraph-multilingual-ssml-lang/gnd.json b/fixtures/paragraph-multilingual-ssml-lang/gnd.json
new file mode 100644
index 0000000..98b0ecd
--- /dev/null
+++ b/fixtures/paragraph-multilingual-ssml-lang/gnd.json
@@ -0,0 +1,9 @@
+{
+  "role": [
+    "paragraph"
+  ],
+  "text": {
+    "ssml": "This job requires a certain <lang xml:lang=\"fr\">savoir faire</lang> that can only be acquired over time.",
+    "language": "en"
+  }
+}
diff --git a/fixtures/paragraph-multilingual-ssml-lang/input.html b/fixtures/paragraph-multilingual-ssml-lang/input.html
new file mode 100644
index 0000000..83539a5
--- /dev/null
+++ b/fixtures/paragraph-multilingual-ssml-lang/input.html
@@ -0,0 +1 @@
+<p>This job requires a certain <em xml:lang="fr">savoir faire</em> that can only be acquired over time.</p>
diff --git a/fixtures/paragraph-multilingual-ssml-lang/meta.json b/fixtures/paragraph-multilingual-ssml-lang/meta.json
new file mode 100644
index 0000000..7922677
--- /dev/null
+++ b/fixtures/paragraph-multilingual-ssml-lang/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "paragraph-multilingual-ssml-lang",
+  "description": "A paragraph with an inline foreign-language phrase, represented via SSML",
+  "role": "paragraph",
+  "rolesCovered": [
+    "paragraph"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/tree/main/examples/read-aloud#multilingual-text",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/paragraph-multilingual-ssml-lang/utterances.json b/fixtures/paragraph-multilingual-ssml-lang/utterances.json
new file mode 100644
index 0000000..30f8c91
--- /dev/null
+++ b/fixtures/paragraph-multilingual-ssml-lang/utterances.json
@@ -0,0 +1,7 @@
+[
+  {
+    "text": "This job requires a certain <lang xml:lang=\"fr\">savoir faire</lang> that can only be acquired over time.",
+    "ssml": true,
+    "language": "en"
+  }
+]
diff --git a/fixtures/paragraph-multilingual-text-children/gnd.json b/fixtures/paragraph-multilingual-text-children/gnd.json
new file mode 100644
index 0000000..20a6282
--- /dev/null
+++ b/fixtures/paragraph-multilingual-text-children/gnd.json
@@ -0,0 +1,25 @@
+{
+  "role": [
+    "paragraph"
+  ],
+  "children": [
+    {
+      "text": {
+        "plain": "This job requires a certain",
+        "language": "en"
+      }
+    },
+    {
+      "text": {
+        "plain": "savoir faire",
+        "language": "fr"
+      }
+    },
+    {
+      "text": {
+        "plain": "that can only be acquired over time.",
+        "language": "en"
+      }
+    }
+  ]
+}
diff --git a/fixtures/paragraph-multilingual-text-children/input.html b/fixtures/paragraph-multilingual-text-children/input.html
new file mode 100644
index 0000000..83539a5
--- /dev/null
+++ b/fixtures/paragraph-multilingual-text-children/input.html
@@ -0,0 +1 @@
+<p>This job requires a certain <em xml:lang="fr">savoir faire</em> that can only be acquired over time.</p>
diff --git a/fixtures/paragraph-multilingual-text-children/meta.json b/fixtures/paragraph-multilingual-text-children/meta.json
new file mode 100644
index 0000000..29a7fc2
--- /dev/null
+++ b/fixtures/paragraph-multilingual-text-children/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "paragraph-multilingual-text-children",
+  "description": "A paragraph with an inline foreign-language phrase, represented as separate text children per language",
+  "role": "paragraph",
+  "rolesCovered": [
+    "paragraph"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/tree/main/examples/read-aloud#multilingual-text",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/paragraph-multilingual-text-children/utterances.json b/fixtures/paragraph-multilingual-text-children/utterances.json
new file mode 100644
index 0000000..bcaf0b6
--- /dev/null
+++ b/fixtures/paragraph-multilingual-text-children/utterances.json
@@ -0,0 +1,14 @@
+[
+  {
+    "text": "This job requires a certain",
+    "language": "en"
+  },
+  {
+    "text": "savoir faire",
+    "language": "fr"
+  },
+  {
+    "text": "that can only be acquired over time.",
+    "language": "en"
+  }
+]
diff --git a/fixtures/part-epub-type/gnd.json b/fixtures/part-epub-type/gnd.json
new file mode 100644
index 0000000..8a2259f
--- /dev/null
+++ b/fixtures/part-epub-type/gnd.json
@@ -0,0 +1,13 @@
+{
+  "role": [
+    "part"
+  ],
+  "children": [
+    {
+      "role": [
+        "heading1"
+      ],
+      "text": "Title of the part"
+    }
+  ]
+}
diff --git a/fixtures/part-epub-type/input.html b/fixtures/part-epub-type/input.html
new file mode 100644
index 0000000..d9c8901
--- /dev/null
+++ b/fixtures/part-epub-type/input.html
@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops">
+<head>
+<meta charset="utf-8"/>
+<title>Fixture</title>
+</head>
+<body>
+<section epub:type="part">
+  <h1>Title of the part</h1>
+</section>
+</body>
+</html>
diff --git a/fixtures/part-epub-type/meta.json b/fixtures/part-epub-type/meta.json
new file mode 100644
index 0000000..75ea413
--- /dev/null
+++ b/fixtures/part-epub-type/meta.json
@@ -0,0 +1,11 @@
+{
+  "id": "part-epub-type",
+  "description": "part role via epub:type=\"part\", containing a heading",
+  "role": "part",
+  "rolesCovered": [
+    "part",
+    "heading1"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/tree/main/examples/read-aloud#sections-and-headers",
+  "inputKind": "document"
+}
diff --git a/fixtures/part-epub-type/utterances.json b/fixtures/part-epub-type/utterances.json
new file mode 100644
index 0000000..0f3abff
--- /dev/null
+++ b/fixtures/part-epub-type/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "Title of the part"
+  }
+]
diff --git a/fixtures/part-role-aria/gnd.json b/fixtures/part-role-aria/gnd.json
new file mode 100644
index 0000000..8a2259f
--- /dev/null
+++ b/fixtures/part-role-aria/gnd.json
@@ -0,0 +1,13 @@
+{
+  "role": [
+    "part"
+  ],
+  "children": [
+    {
+      "role": [
+        "heading1"
+      ],
+      "text": "Title of the part"
+    }
+  ]
+}
diff --git a/fixtures/part-role-aria/input.html b/fixtures/part-role-aria/input.html
new file mode 100644
index 0000000..fd78196
--- /dev/null
+++ b/fixtures/part-role-aria/input.html
@@ -0,0 +1,3 @@
+<section role="doc-part">
+  <h1>Title of the part</h1>
+</section>
diff --git a/fixtures/part-role-aria/meta.json b/fixtures/part-role-aria/meta.json
new file mode 100644
index 0000000..4a06ebd
--- /dev/null
+++ b/fixtures/part-role-aria/meta.json
@@ -0,0 +1,11 @@
+{
+  "id": "part-role-aria",
+  "description": "part role via explicit ARIA role=\"doc-part\", containing a heading",
+  "role": "part",
+  "rolesCovered": [
+    "part",
+    "heading1"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/part-role-aria/utterances.json b/fixtures/part-role-aria/utterances.json
new file mode 100644
index 0000000..0f3abff
--- /dev/null
+++ b/fixtures/part-role-aria/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "Title of the part"
+  }
+]
diff --git a/fixtures/preface-epub-type/gnd.json b/fixtures/preface-epub-type/gnd.json
new file mode 100644
index 0000000..20e7432
--- /dev/null
+++ b/fixtures/preface-epub-type/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "preface"
+  ],
+  "text": "This edition adds a chapter on automation."
+}
diff --git a/fixtures/preface-epub-type/input.html b/fixtures/preface-epub-type/input.html
new file mode 100644
index 0000000..b7a8f66
--- /dev/null
+++ b/fixtures/preface-epub-type/input.html
@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops">
+<head>
+<meta charset="utf-8"/>
+<title>Fixture</title>
+</head>
+<body>
+<div epub:type="preface">This edition adds a chapter on automation.</div>
+</body>
+</html>
diff --git a/fixtures/preface-epub-type/meta.json b/fixtures/preface-epub-type/meta.json
new file mode 100644
index 0000000..00ca0ec
--- /dev/null
+++ b/fixtures/preface-epub-type/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "preface-epub-type",
+  "description": "preface role via epub:type=\"preface\"",
+  "role": "preface",
+  "rolesCovered": [
+    "preface"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "document"
+}
diff --git a/fixtures/preface-epub-type/utterances.json b/fixtures/preface-epub-type/utterances.json
new file mode 100644
index 0000000..72b6951
--- /dev/null
+++ b/fixtures/preface-epub-type/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "This edition adds a chapter on automation."
+  }
+]
diff --git a/fixtures/preface-role-aria/gnd.json b/fixtures/preface-role-aria/gnd.json
new file mode 100644
index 0000000..20e7432
--- /dev/null
+++ b/fixtures/preface-role-aria/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "preface"
+  ],
+  "text": "This edition adds a chapter on automation."
+}
diff --git a/fixtures/preface-role-aria/input.html b/fixtures/preface-role-aria/input.html
new file mode 100644
index 0000000..2827887
--- /dev/null
+++ b/fixtures/preface-role-aria/input.html
@@ -0,0 +1 @@
+<div role="doc-preface">This edition adds a chapter on automation.</div>
diff --git a/fixtures/preface-role-aria/meta.json b/fixtures/preface-role-aria/meta.json
new file mode 100644
index 0000000..603742e
--- /dev/null
+++ b/fixtures/preface-role-aria/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "preface-role-aria",
+  "description": "preface role via explicit ARIA role=\"doc-preface\"",
+  "role": "preface",
+  "rolesCovered": [
+    "preface"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/preface-role-aria/utterances.json b/fixtures/preface-role-aria/utterances.json
new file mode 100644
index 0000000..72b6951
--- /dev/null
+++ b/fixtures/preface-role-aria/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "This edition adds a chapter on automation."
+  }
+]
diff --git a/fixtures/preformatted-html-native/gnd.json b/fixtures/preformatted-html-native/gnd.json
new file mode 100644
index 0000000..a98e469
--- /dev/null
+++ b/fixtures/preformatted-html-native/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "preformatted"
+  ],
+  "text": "  10 PRINT \"HELLO\"\n  20 GOTO 10"
+}
diff --git a/fixtures/preformatted-html-native/input.html b/fixtures/preformatted-html-native/input.html
new file mode 100644
index 0000000..ab3604d
--- /dev/null
+++ b/fixtures/preformatted-html-native/input.html
@@ -0,0 +1,2 @@
+<pre>  10 PRINT "HELLO"
+  20 GOTO 10</pre>
diff --git a/fixtures/preformatted-html-native/meta.json b/fixtures/preformatted-html-native/meta.json
new file mode 100644
index 0000000..eb242c7
--- /dev/null
+++ b/fixtures/preformatted-html-native/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "preformatted-html-native",
+  "description": "preformatted role via native <pre> element",
+  "role": "preformatted",
+  "rolesCovered": [
+    "preformatted"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/preformatted-html-native/utterances.json b/fixtures/preformatted-html-native/utterances.json
new file mode 100644
index 0000000..39df182
--- /dev/null
+++ b/fixtures/preformatted-html-native/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "  10 PRINT \"HELLO\"\n  20 GOTO 10"
+  }
+]
diff --git a/fixtures/presentation-role-aria/gnd.json b/fixtures/presentation-role-aria/gnd.json
new file mode 100644
index 0000000..cbb4223
--- /dev/null
+++ b/fixtures/presentation-role-aria/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "presentation"
+  ],
+  "text": "Decorative content with no semantic meaning."
+}
diff --git a/fixtures/presentation-role-aria/input.html b/fixtures/presentation-role-aria/input.html
new file mode 100644
index 0000000..60e0372
--- /dev/null
+++ b/fixtures/presentation-role-aria/input.html
@@ -0,0 +1 @@
+<div role="presentation">Decorative content with no semantic meaning.</div>
diff --git a/fixtures/presentation-role-aria/meta.json b/fixtures/presentation-role-aria/meta.json
new file mode 100644
index 0000000..1cf1a96
--- /dev/null
+++ b/fixtures/presentation-role-aria/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "presentation-role-aria",
+  "description": "presentation role via explicit ARIA role=\"presentation\"",
+  "role": "presentation",
+  "rolesCovered": [
+    "presentation"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/presentation-role-aria/utterances.json b/fixtures/presentation-role-aria/utterances.json
new file mode 100644
index 0000000..c369476
--- /dev/null
+++ b/fixtures/presentation-role-aria/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "Decorative content with no semantic meaning."
+  }
+]
diff --git a/fixtures/prologue-epub-type/gnd.json b/fixtures/prologue-epub-type/gnd.json
new file mode 100644
index 0000000..46d6f5b
--- /dev/null
+++ b/fixtures/prologue-epub-type/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "prologue"
+  ],
+  "text": "Before the lamp was ever lit, the rock was already feared."
+}
diff --git a/fixtures/prologue-epub-type/input.html b/fixtures/prologue-epub-type/input.html
new file mode 100644
index 0000000..61aeacb
--- /dev/null
+++ b/fixtures/prologue-epub-type/input.html
@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops">
+<head>
+<meta charset="utf-8"/>
+<title>Fixture</title>
+</head>
+<body>
+<div epub:type="prologue">Before the lamp was ever lit, the rock was already feared.</div>
+</body>
+</html>
diff --git a/fixtures/prologue-epub-type/meta.json b/fixtures/prologue-epub-type/meta.json
new file mode 100644
index 0000000..a5a91e7
--- /dev/null
+++ b/fixtures/prologue-epub-type/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "prologue-epub-type",
+  "description": "prologue role via epub:type=\"prologue\"",
+  "role": "prologue",
+  "rolesCovered": [
+    "prologue"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "document"
+}
diff --git a/fixtures/prologue-epub-type/utterances.json b/fixtures/prologue-epub-type/utterances.json
new file mode 100644
index 0000000..d246a2e
--- /dev/null
+++ b/fixtures/prologue-epub-type/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "Before the lamp was ever lit, the rock was already feared."
+  }
+]
diff --git a/fixtures/prologue-role-aria/gnd.json b/fixtures/prologue-role-aria/gnd.json
new file mode 100644
index 0000000..46d6f5b
--- /dev/null
+++ b/fixtures/prologue-role-aria/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "prologue"
+  ],
+  "text": "Before the lamp was ever lit, the rock was already feared."
+}
diff --git a/fixtures/prologue-role-aria/input.html b/fixtures/prologue-role-aria/input.html
new file mode 100644
index 0000000..ebb5b7a
--- /dev/null
+++ b/fixtures/prologue-role-aria/input.html
@@ -0,0 +1 @@
+<div role="doc-prologue">Before the lamp was ever lit, the rock was already feared.</div>
diff --git a/fixtures/prologue-role-aria/meta.json b/fixtures/prologue-role-aria/meta.json
new file mode 100644
index 0000000..d20dd47
--- /dev/null
+++ b/fixtures/prologue-role-aria/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "prologue-role-aria",
+  "description": "prologue role via explicit ARIA role=\"doc-prologue\"",
+  "role": "prologue",
+  "rolesCovered": [
+    "prologue"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/prologue-role-aria/utterances.json b/fixtures/prologue-role-aria/utterances.json
new file mode 100644
index 0000000..d246a2e
--- /dev/null
+++ b/fixtures/prologue-role-aria/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "Before the lamp was ever lit, the rock was already feared."
+  }
+]
diff --git a/fixtures/pullquote-epub-type/gnd.json b/fixtures/pullquote-epub-type/gnd.json
new file mode 100644
index 0000000..d79532c
--- /dev/null
+++ b/fixtures/pullquote-epub-type/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "pullquote"
+  ],
+  "text": "The lamp still turns, though no one climbs the stairs anymore."
+}
diff --git a/fixtures/pullquote-epub-type/input.html b/fixtures/pullquote-epub-type/input.html
new file mode 100644
index 0000000..48ec5aa
--- /dev/null
+++ b/fixtures/pullquote-epub-type/input.html
@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops">
+<head>
+<meta charset="utf-8"/>
+<title>Fixture</title>
+</head>
+<body>
+<aside epub:type="pullquote">The lamp still turns, though no one climbs the stairs anymore.</aside>
+</body>
+</html>
diff --git a/fixtures/pullquote-epub-type/meta.json b/fixtures/pullquote-epub-type/meta.json
new file mode 100644
index 0000000..c56451e
--- /dev/null
+++ b/fixtures/pullquote-epub-type/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "pullquote-epub-type",
+  "description": "pullquote role via epub:type=\"pullquote\" on an <aside>",
+  "role": "pullquote",
+  "rolesCovered": [
+    "pullquote"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "document"
+}
diff --git a/fixtures/pullquote-epub-type/utterances.json b/fixtures/pullquote-epub-type/utterances.json
new file mode 100644
index 0000000..bbbf7ab
--- /dev/null
+++ b/fixtures/pullquote-epub-type/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "The lamp still turns, though no one climbs the stairs anymore."
+  }
+]
diff --git a/fixtures/pullquote-role-aria/gnd.json b/fixtures/pullquote-role-aria/gnd.json
new file mode 100644
index 0000000..d79532c
--- /dev/null
+++ b/fixtures/pullquote-role-aria/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "pullquote"
+  ],
+  "text": "The lamp still turns, though no one climbs the stairs anymore."
+}
diff --git a/fixtures/pullquote-role-aria/input.html b/fixtures/pullquote-role-aria/input.html
new file mode 100644
index 0000000..49d9d7f
--- /dev/null
+++ b/fixtures/pullquote-role-aria/input.html
@@ -0,0 +1 @@
+<div role="doc-pullquote">The lamp still turns, though no one climbs the stairs anymore.</div>
diff --git a/fixtures/pullquote-role-aria/meta.json b/fixtures/pullquote-role-aria/meta.json
new file mode 100644
index 0000000..b576ae7
--- /dev/null
+++ b/fixtures/pullquote-role-aria/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "pullquote-role-aria",
+  "description": "pullquote role via explicit ARIA role=\"doc-pullquote\"",
+  "role": "pullquote",
+  "rolesCovered": [
+    "pullquote"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/pullquote-role-aria/utterances.json b/fixtures/pullquote-role-aria/utterances.json
new file mode 100644
index 0000000..bbbf7ab
--- /dev/null
+++ b/fixtures/pullquote-role-aria/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "The lamp still turns, though no one climbs the stairs anymore."
+  }
+]
diff --git a/fixtures/qna-epub-type/gnd.json b/fixtures/qna-epub-type/gnd.json
new file mode 100644
index 0000000..e22b599
--- /dev/null
+++ b/fixtures/qna-epub-type/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "qna"
+  ],
+  "text": "Q: How often was the lamp refueled? A: Nightly, by hand."
+}
diff --git a/fixtures/qna-epub-type/input.html b/fixtures/qna-epub-type/input.html
new file mode 100644
index 0000000..9334086
--- /dev/null
+++ b/fixtures/qna-epub-type/input.html
@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops">
+<head>
+<meta charset="utf-8"/>
+<title>Fixture</title>
+</head>
+<body>
+<section epub:type="qna">Q: How often was the lamp refueled? A: Nightly, by hand.</section>
+</body>
+</html>
diff --git a/fixtures/qna-epub-type/meta.json b/fixtures/qna-epub-type/meta.json
new file mode 100644
index 0000000..167aa1c
--- /dev/null
+++ b/fixtures/qna-epub-type/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "qna-epub-type",
+  "description": "qna role via epub:type=\"qna\" on a <section>",
+  "role": "qna",
+  "rolesCovered": [
+    "qna"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "document"
+}
diff --git a/fixtures/qna-epub-type/utterances.json b/fixtures/qna-epub-type/utterances.json
new file mode 100644
index 0000000..6b8def2
--- /dev/null
+++ b/fixtures/qna-epub-type/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "Q: How often was the lamp refueled? A: Nightly, by hand."
+  }
+]
diff --git a/fixtures/qna-role-aria/gnd.json b/fixtures/qna-role-aria/gnd.json
new file mode 100644
index 0000000..e22b599
--- /dev/null
+++ b/fixtures/qna-role-aria/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "qna"
+  ],
+  "text": "Q: How often was the lamp refueled? A: Nightly, by hand."
+}
diff --git a/fixtures/qna-role-aria/input.html b/fixtures/qna-role-aria/input.html
new file mode 100644
index 0000000..4e29c0c
--- /dev/null
+++ b/fixtures/qna-role-aria/input.html
@@ -0,0 +1 @@
+<div role="doc-qna">Q: How often was the lamp refueled? A: Nightly, by hand.</div>
diff --git a/fixtures/qna-role-aria/meta.json b/fixtures/qna-role-aria/meta.json
new file mode 100644
index 0000000..acc5f16
--- /dev/null
+++ b/fixtures/qna-role-aria/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "qna-role-aria",
+  "description": "qna role via explicit ARIA role=\"doc-qna\"",
+  "role": "qna",
+  "rolesCovered": [
+    "qna"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/qna-role-aria/utterances.json b/fixtures/qna-role-aria/utterances.json
new file mode 100644
index 0000000..6b8def2
--- /dev/null
+++ b/fixtures/qna-role-aria/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "Q: How often was the lamp refueled? A: Nightly, by hand."
+  }
+]
diff --git a/fixtures/region-role-aria/gnd.json b/fixtures/region-role-aria/gnd.json
new file mode 100644
index 0000000..51c1e8a
--- /dev/null
+++ b/fixtures/region-role-aria/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "region"
+  ],
+  "text": "A named region of interest within the page."
+}
diff --git a/fixtures/region-role-aria/input.html b/fixtures/region-role-aria/input.html
new file mode 100644
index 0000000..3c029d0
--- /dev/null
+++ b/fixtures/region-role-aria/input.html
@@ -0,0 +1 @@
+<div role="region">A named region of interest within the page.</div>
diff --git a/fixtures/region-role-aria/meta.json b/fixtures/region-role-aria/meta.json
new file mode 100644
index 0000000..510a5eb
--- /dev/null
+++ b/fixtures/region-role-aria/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "region-role-aria",
+  "description": "region role via explicit ARIA role=\"region\"",
+  "role": "region",
+  "rolesCovered": [
+    "region"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/region-role-aria/utterances.json b/fixtures/region-role-aria/utterances.json
new file mode 100644
index 0000000..1b71593
--- /dev/null
+++ b/fixtures/region-role-aria/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "A named region of interest within the page."
+  }
+]
diff --git a/fixtures/separator-html-native/gnd.json b/fixtures/separator-html-native/gnd.json
new file mode 100644
index 0000000..4db8f26
--- /dev/null
+++ b/fixtures/separator-html-native/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "separator"
+  ],
+  "text": ""
+}
diff --git a/fixtures/separator-html-native/input.html b/fixtures/separator-html-native/input.html
new file mode 100644
index 0000000..e123ba7
--- /dev/null
+++ b/fixtures/separator-html-native/input.html
@@ -0,0 +1 @@
+<hr>
diff --git a/fixtures/separator-html-native/meta.json b/fixtures/separator-html-native/meta.json
new file mode 100644
index 0000000..2fa0fb5
--- /dev/null
+++ b/fixtures/separator-html-native/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "separator-html-native",
+  "description": "separator role via native <hr> element; a purely visual divider with no read-aloud content",
+  "role": "separator",
+  "rolesCovered": [
+    "separator"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/separator-html-native/utterances.json b/fixtures/separator-html-native/utterances.json
new file mode 100644
index 0000000..fe51488
--- /dev/null
+++ b/fixtures/separator-html-native/utterances.json
@@ -0,0 +1 @@
+[]
diff --git a/fixtures/separator-role-aria/gnd.json b/fixtures/separator-role-aria/gnd.json
new file mode 100644
index 0000000..76e5e43
--- /dev/null
+++ b/fixtures/separator-role-aria/gnd.json
@@ -0,0 +1,5 @@
+{
+  "role": [
+    "separator"
+  ]
+}
diff --git a/fixtures/separator-role-aria/input.html b/fixtures/separator-role-aria/input.html
new file mode 100644
index 0000000..0d1f4de
--- /dev/null
+++ b/fixtures/separator-role-aria/input.html
@@ -0,0 +1 @@
+<div role="separator"></div>
diff --git a/fixtures/separator-role-aria/meta.json b/fixtures/separator-role-aria/meta.json
new file mode 100644
index 0000000..3ec11d5
--- /dev/null
+++ b/fixtures/separator-role-aria/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "separator-role-aria",
+  "description": "separator role via explicit ARIA role=\"separator\"; a purely visual divider with no read-aloud content",
+  "role": "separator",
+  "rolesCovered": [
+    "separator"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/separator-role-aria/utterances.json b/fixtures/separator-role-aria/utterances.json
new file mode 100644
index 0000000..fe51488
--- /dev/null
+++ b/fixtures/separator-role-aria/utterances.json
@@ -0,0 +1 @@
+[]
diff --git a/fixtures/subtitle-epub-type/gnd.json b/fixtures/subtitle-epub-type/gnd.json
new file mode 100644
index 0000000..8e35c8f
--- /dev/null
+++ b/fixtures/subtitle-epub-type/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "subtitle"
+  ],
+  "text": "A History of Coastal Lights"
+}
diff --git a/fixtures/subtitle-epub-type/input.html b/fixtures/subtitle-epub-type/input.html
new file mode 100644
index 0000000..40daa04
--- /dev/null
+++ b/fixtures/subtitle-epub-type/input.html
@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops">
+<head>
+<meta charset="utf-8"/>
+<title>Fixture</title>
+</head>
+<body>
+<div epub:type="subtitle">A History of Coastal Lights</div>
+</body>
+</html>
diff --git a/fixtures/subtitle-epub-type/meta.json b/fixtures/subtitle-epub-type/meta.json
new file mode 100644
index 0000000..bbe349c
--- /dev/null
+++ b/fixtures/subtitle-epub-type/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "subtitle-epub-type",
+  "description": "subtitle role via epub:type=\"subtitle\"",
+  "role": "subtitle",
+  "rolesCovered": [
+    "subtitle"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "document"
+}
diff --git a/fixtures/subtitle-epub-type/utterances.json b/fixtures/subtitle-epub-type/utterances.json
new file mode 100644
index 0000000..deaf58a
--- /dev/null
+++ b/fixtures/subtitle-epub-type/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "A History of Coastal Lights"
+  }
+]
diff --git a/fixtures/subtitle-role-aria/gnd.json b/fixtures/subtitle-role-aria/gnd.json
new file mode 100644
index 0000000..8e35c8f
--- /dev/null
+++ b/fixtures/subtitle-role-aria/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "subtitle"
+  ],
+  "text": "A History of Coastal Lights"
+}
diff --git a/fixtures/subtitle-role-aria/input.html b/fixtures/subtitle-role-aria/input.html
new file mode 100644
index 0000000..790129e
--- /dev/null
+++ b/fixtures/subtitle-role-aria/input.html
@@ -0,0 +1 @@
+<div role="doc-subtitle">A History of Coastal Lights</div>
diff --git a/fixtures/subtitle-role-aria/meta.json b/fixtures/subtitle-role-aria/meta.json
new file mode 100644
index 0000000..3c38c3d
--- /dev/null
+++ b/fixtures/subtitle-role-aria/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "subtitle-role-aria",
+  "description": "subtitle role via explicit ARIA role=\"doc-subtitle\"",
+  "role": "subtitle",
+  "rolesCovered": [
+    "subtitle"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/subtitle-role-aria/utterances.json b/fixtures/subtitle-role-aria/utterances.json
new file mode 100644
index 0000000..deaf58a
--- /dev/null
+++ b/fixtures/subtitle-role-aria/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "A History of Coastal Lights"
+  }
+]
diff --git a/fixtures/summary-html-native/gnd.json b/fixtures/summary-html-native/gnd.json
new file mode 100644
index 0000000..306763a
--- /dev/null
+++ b/fixtures/summary-html-native/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "summary"
+  ],
+  "text": "Click to expand"
+}
diff --git a/fixtures/summary-html-native/input.html b/fixtures/summary-html-native/input.html
new file mode 100644
index 0000000..aec1aec
--- /dev/null
+++ b/fixtures/summary-html-native/input.html
@@ -0,0 +1 @@
+<summary>Click to expand</summary>
diff --git a/fixtures/summary-html-native/meta.json b/fixtures/summary-html-native/meta.json
new file mode 100644
index 0000000..6724e26
--- /dev/null
+++ b/fixtures/summary-html-native/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "summary-html-native",
+  "description": "summary role via native <summary> element",
+  "role": "summary",
+  "rolesCovered": [
+    "summary"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/summary-html-native/utterances.json b/fixtures/summary-html-native/utterances.json
new file mode 100644
index 0000000..fd1cc76
--- /dev/null
+++ b/fixtures/summary-html-native/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "Click to expand"
+  }
+]
diff --git a/fixtures/table-html-native/gnd.json b/fixtures/table-html-native/gnd.json
new file mode 100644
index 0000000..ec9b8e6
--- /dev/null
+++ b/fixtures/table-html-native/gnd.json
@@ -0,0 +1,64 @@
+{
+  "role": [
+    "table"
+  ],
+  "children": [
+    {
+      "role": [
+        "row"
+      ],
+      "children": [
+        {
+          "role": [
+            "columnheader"
+          ],
+          "text": "Name"
+        },
+        {
+          "role": [
+            "columnheader"
+          ],
+          "text": "Role"
+        }
+      ]
+    },
+    {
+      "role": [
+        "row"
+      ],
+      "children": [
+        {
+          "role": [
+            "cell"
+          ],
+          "text": "Ada"
+        },
+        {
+          "role": [
+            "cell"
+          ],
+          "text": "Engineer"
+        }
+      ]
+    },
+    {
+      "role": [
+        "row"
+      ],
+      "children": [
+        {
+          "role": [
+            "cell"
+          ],
+          "text": "Grace"
+        },
+        {
+          "role": [
+            "cell"
+          ],
+          "text": "Admiral"
+        }
+      ]
+    }
+  ]
+}
diff --git a/fixtures/table-html-native/input.html b/fixtures/table-html-native/input.html
new file mode 100644
index 0000000..af33a76
--- /dev/null
+++ b/fixtures/table-html-native/input.html
@@ -0,0 +1,5 @@
+<table>
+  <tr><th scope="col">Name</th><th scope="col">Role</th></tr>
+  <tr><td>Ada</td><td>Engineer</td></tr>
+  <tr><td>Grace</td><td>Admiral</td></tr>
+</table>
diff --git a/fixtures/table-html-native/meta.json b/fixtures/table-html-native/meta.json
new file mode 100644
index 0000000..b2593c5
--- /dev/null
+++ b/fixtures/table-html-native/meta.json
@@ -0,0 +1,13 @@
+{
+  "id": "table-html-native",
+  "description": "A table with a header row, via native <table>/<tr>/<th>/<td>",
+  "role": "table",
+  "rolesCovered": [
+    "table",
+    "row",
+    "columnheader",
+    "cell"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/tree/main/examples/read-aloud",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/table-html-native/utterances.json b/fixtures/table-html-native/utterances.json
new file mode 100644
index 0000000..bcc7105
--- /dev/null
+++ b/fixtures/table-html-native/utterances.json
@@ -0,0 +1,20 @@
+[
+  {
+    "text": "Name"
+  },
+  {
+    "text": "Role"
+  },
+  {
+    "text": "Ada"
+  },
+  {
+    "text": "Engineer"
+  },
+  {
+    "text": "Grace"
+  },
+  {
+    "text": "Admiral"
+  }
+]
diff --git a/fixtures/table-role-aria/gnd.json b/fixtures/table-role-aria/gnd.json
new file mode 100644
index 0000000..ec9b8e6
--- /dev/null
+++ b/fixtures/table-role-aria/gnd.json
@@ -0,0 +1,64 @@
+{
+  "role": [
+    "table"
+  ],
+  "children": [
+    {
+      "role": [
+        "row"
+      ],
+      "children": [
+        {
+          "role": [
+            "columnheader"
+          ],
+          "text": "Name"
+        },
+        {
+          "role": [
+            "columnheader"
+          ],
+          "text": "Role"
+        }
+      ]
+    },
+    {
+      "role": [
+        "row"
+      ],
+      "children": [
+        {
+          "role": [
+            "cell"
+          ],
+          "text": "Ada"
+        },
+        {
+          "role": [
+            "cell"
+          ],
+          "text": "Engineer"
+        }
+      ]
+    },
+    {
+      "role": [
+        "row"
+      ],
+      "children": [
+        {
+          "role": [
+            "cell"
+          ],
+          "text": "Grace"
+        },
+        {
+          "role": [
+            "cell"
+          ],
+          "text": "Admiral"
+        }
+      ]
+    }
+  ]
+}
diff --git a/fixtures/table-role-aria/input.html b/fixtures/table-role-aria/input.html
new file mode 100644
index 0000000..ada669e
--- /dev/null
+++ b/fixtures/table-role-aria/input.html
@@ -0,0 +1,5 @@
+<div role="table">
+  <div role="row"><div role="columnheader">Name</div><div role="columnheader">Role</div></div>
+  <div role="row"><div role="cell">Ada</div><div role="cell">Engineer</div></div>
+  <div role="row"><div role="cell">Grace</div><div role="cell">Admiral</div></div>
+</div>
diff --git a/fixtures/table-role-aria/meta.json b/fixtures/table-role-aria/meta.json
new file mode 100644
index 0000000..8723961
--- /dev/null
+++ b/fixtures/table-role-aria/meta.json
@@ -0,0 +1,13 @@
+{
+  "id": "table-role-aria",
+  "description": "A table with a header row, via explicit ARIA table/row/columnheader/cell roles",
+  "role": "table",
+  "rolesCovered": [
+    "table",
+    "row",
+    "columnheader",
+    "cell"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/tree/main/examples/read-aloud",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/table-role-aria/utterances.json b/fixtures/table-role-aria/utterances.json
new file mode 100644
index 0000000..bcc7105
--- /dev/null
+++ b/fixtures/table-role-aria/utterances.json
@@ -0,0 +1,20 @@
+[
+  {
+    "text": "Name"
+  },
+  {
+    "text": "Role"
+  },
+  {
+    "text": "Ada"
+  },
+  {
+    "text": "Engineer"
+  },
+  {
+    "text": "Grace"
+  },
+  {
+    "text": "Admiral"
+  }
+]
diff --git a/fixtures/term-epub-type/gnd.json b/fixtures/term-epub-type/gnd.json
new file mode 100644
index 0000000..3eaba6c
--- /dev/null
+++ b/fixtures/term-epub-type/gnd.json
@@ -0,0 +1,13 @@
+{
+  "role": [
+    "glossary"
+  ],
+  "children": [
+    {
+      "role": [
+        "term"
+      ],
+      "text": "lighthouse"
+    }
+  ]
+}
diff --git a/fixtures/term-epub-type/input.html b/fixtures/term-epub-type/input.html
new file mode 100644
index 0000000..90dea64
--- /dev/null
+++ b/fixtures/term-epub-type/input.html
@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops">
+<head>
+<meta charset="utf-8"/>
+<title>Fixture</title>
+</head>
+<body>
+<dl epub:type="glossary">
+  <dt epub:type="glossterm">lighthouse</dt>
+</dl>
+</body>
+</html>
diff --git a/fixtures/term-epub-type/meta.json b/fixtures/term-epub-type/meta.json
new file mode 100644
index 0000000..abf8363
--- /dev/null
+++ b/fixtures/term-epub-type/meta.json
@@ -0,0 +1,11 @@
+{
+  "id": "term-epub-type",
+  "description": "term role via epub:type=\"glossterm\" on a <dt>, nested in a <dl epub:type=\"glossary\">",
+  "role": "term",
+  "rolesCovered": [
+    "term",
+    "glossary"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "document"
+}
diff --git a/fixtures/term-epub-type/utterances.json b/fixtures/term-epub-type/utterances.json
new file mode 100644
index 0000000..c008575
--- /dev/null
+++ b/fixtures/term-epub-type/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "lighthouse"
+  }
+]
diff --git a/fixtures/term-html-native/gnd.json b/fixtures/term-html-native/gnd.json
new file mode 100644
index 0000000..df965e7
--- /dev/null
+++ b/fixtures/term-html-native/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "term"
+  ],
+  "text": "lighthouse"
+}
diff --git a/fixtures/term-html-native/input.html b/fixtures/term-html-native/input.html
new file mode 100644
index 0000000..bdc08f6
--- /dev/null
+++ b/fixtures/term-html-native/input.html
@@ -0,0 +1 @@
+<dfn>lighthouse</dfn>
diff --git a/fixtures/term-html-native/meta.json b/fixtures/term-html-native/meta.json
new file mode 100644
index 0000000..754ca1f
--- /dev/null
+++ b/fixtures/term-html-native/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "term-html-native",
+  "description": "term role via native <dfn> element",
+  "role": "term",
+  "rolesCovered": [
+    "term"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/term-html-native/utterances.json b/fixtures/term-html-native/utterances.json
new file mode 100644
index 0000000..c008575
--- /dev/null
+++ b/fixtures/term-html-native/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "lighthouse"
+  }
+]
diff --git a/fixtures/term-role-aria/gnd.json b/fixtures/term-role-aria/gnd.json
new file mode 100644
index 0000000..df965e7
--- /dev/null
+++ b/fixtures/term-role-aria/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "term"
+  ],
+  "text": "lighthouse"
+}
diff --git a/fixtures/term-role-aria/input.html b/fixtures/term-role-aria/input.html
new file mode 100644
index 0000000..6ad2bad
--- /dev/null
+++ b/fixtures/term-role-aria/input.html
@@ -0,0 +1 @@
+<div role="term">lighthouse</div>
diff --git a/fixtures/term-role-aria/meta.json b/fixtures/term-role-aria/meta.json
new file mode 100644
index 0000000..95f949f
--- /dev/null
+++ b/fixtures/term-role-aria/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "term-role-aria",
+  "description": "term role via explicit ARIA role=\"term\"",
+  "role": "term",
+  "rolesCovered": [
+    "term"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/term-role-aria/utterances.json b/fixtures/term-role-aria/utterances.json
new file mode 100644
index 0000000..c008575
--- /dev/null
+++ b/fixtures/term-role-aria/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "lighthouse"
+  }
+]
diff --git a/fixtures/tip-epub-type/gnd.json b/fixtures/tip-epub-type/gnd.json
new file mode 100644
index 0000000..703f951
--- /dev/null
+++ b/fixtures/tip-epub-type/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "tip"
+  ],
+  "text": "Tip: wind the mechanism fully before dusk."
+}
diff --git a/fixtures/tip-epub-type/input.html b/fixtures/tip-epub-type/input.html
new file mode 100644
index 0000000..f1be368
--- /dev/null
+++ b/fixtures/tip-epub-type/input.html
@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops">
+<head>
+<meta charset="utf-8"/>
+<title>Fixture</title>
+</head>
+<body>
+<aside epub:type="tip">Tip: wind the mechanism fully before dusk.</aside>
+</body>
+</html>
diff --git a/fixtures/tip-epub-type/meta.json b/fixtures/tip-epub-type/meta.json
new file mode 100644
index 0000000..6586391
--- /dev/null
+++ b/fixtures/tip-epub-type/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "tip-epub-type",
+  "description": "tip role via epub:type=\"tip\" on an <aside>",
+  "role": "tip",
+  "rolesCovered": [
+    "tip"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "document"
+}
diff --git a/fixtures/tip-epub-type/utterances.json b/fixtures/tip-epub-type/utterances.json
new file mode 100644
index 0000000..0af016d
--- /dev/null
+++ b/fixtures/tip-epub-type/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "Tip: wind the mechanism fully before dusk."
+  }
+]
diff --git a/fixtures/tip-role-aria/gnd.json b/fixtures/tip-role-aria/gnd.json
new file mode 100644
index 0000000..703f951
--- /dev/null
+++ b/fixtures/tip-role-aria/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "tip"
+  ],
+  "text": "Tip: wind the mechanism fully before dusk."
+}
diff --git a/fixtures/tip-role-aria/input.html b/fixtures/tip-role-aria/input.html
new file mode 100644
index 0000000..63efd12
--- /dev/null
+++ b/fixtures/tip-role-aria/input.html
@@ -0,0 +1 @@
+<div role="doc-tip">Tip: wind the mechanism fully before dusk.</div>
diff --git a/fixtures/tip-role-aria/meta.json b/fixtures/tip-role-aria/meta.json
new file mode 100644
index 0000000..f19044e
--- /dev/null
+++ b/fixtures/tip-role-aria/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "tip-role-aria",
+  "description": "tip role via explicit ARIA role=\"doc-tip\"",
+  "role": "tip",
+  "rolesCovered": [
+    "tip"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/tip-role-aria/utterances.json b/fixtures/tip-role-aria/utterances.json
new file mode 100644
index 0000000..0af016d
--- /dev/null
+++ b/fixtures/tip-role-aria/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "Tip: wind the mechanism fully before dusk."
+  }
+]
diff --git a/fixtures/toc-epub-type/gnd.json b/fixtures/toc-epub-type/gnd.json
new file mode 100644
index 0000000..cd1116a
--- /dev/null
+++ b/fixtures/toc-epub-type/gnd.json
@@ -0,0 +1,35 @@
+{
+  "role": [
+    "toc"
+  ],
+  "children": [
+    {
+      "role": [
+        "list"
+      ],
+      "children": [
+        {
+          "role": [
+            "listItem"
+          ],
+          "text": "Chapter One",
+          "textref": "chapter1.xhtml"
+        },
+        {
+          "role": [
+            "listItem"
+          ],
+          "text": "Chapter Two",
+          "textref": "chapter2.xhtml"
+        },
+        {
+          "role": [
+            "listItem"
+          ],
+          "text": "Chapter Three",
+          "textref": "chapter3.xhtml"
+        }
+      ]
+    }
+  ]
+}
diff --git a/fixtures/toc-epub-type/input.html b/fixtures/toc-epub-type/input.html
new file mode 100644
index 0000000..4ca6698
--- /dev/null
+++ b/fixtures/toc-epub-type/input.html
@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops">
+<head>
+<meta charset="utf-8"/>
+<title>Fixture</title>
+</head>
+<body>
+<nav epub:type="toc">
+  <ol>
+    <li><a href="chapter1.xhtml">Chapter One</a></li>
+    <li><a href="chapter2.xhtml">Chapter Two</a></li>
+    <li><a href="chapter3.xhtml">Chapter Three</a></li>
+  </ol>
+</nav>
+</body>
+</html>
diff --git a/fixtures/toc-epub-type/meta.json b/fixtures/toc-epub-type/meta.json
new file mode 100644
index 0000000..2f6bef8
--- /dev/null
+++ b/fixtures/toc-epub-type/meta.json
@@ -0,0 +1,12 @@
+{
+  "id": "toc-epub-type",
+  "description": "A table-of-contents navigation list, containing links to sectional headings, via epub:type",
+  "role": "toc",
+  "rolesCovered": [
+    "toc",
+    "list",
+    "listItem"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "document"
+}
diff --git a/fixtures/toc-epub-type/utterances.json b/fixtures/toc-epub-type/utterances.json
new file mode 100644
index 0000000..492da85
--- /dev/null
+++ b/fixtures/toc-epub-type/utterances.json
@@ -0,0 +1,11 @@
+[
+  {
+    "text": "Chapter One"
+  },
+  {
+    "text": "Chapter Two"
+  },
+  {
+    "text": "Chapter Three"
+  }
+]
diff --git a/fixtures/toc-role-aria/gnd.json b/fixtures/toc-role-aria/gnd.json
new file mode 100644
index 0000000..cd1116a
--- /dev/null
+++ b/fixtures/toc-role-aria/gnd.json
@@ -0,0 +1,35 @@
+{
+  "role": [
+    "toc"
+  ],
+  "children": [
+    {
+      "role": [
+        "list"
+      ],
+      "children": [
+        {
+          "role": [
+            "listItem"
+          ],
+          "text": "Chapter One",
+          "textref": "chapter1.xhtml"
+        },
+        {
+          "role": [
+            "listItem"
+          ],
+          "text": "Chapter Two",
+          "textref": "chapter2.xhtml"
+        },
+        {
+          "role": [
+            "listItem"
+          ],
+          "text": "Chapter Three",
+          "textref": "chapter3.xhtml"
+        }
+      ]
+    }
+  ]
+}
diff --git a/fixtures/toc-role-aria/input.html b/fixtures/toc-role-aria/input.html
new file mode 100644
index 0000000..0f9d637
--- /dev/null
+++ b/fixtures/toc-role-aria/input.html
@@ -0,0 +1,7 @@
+<nav role="doc-toc">
+  <ol>
+    <li><a href="chapter1.xhtml">Chapter One</a></li>
+    <li><a href="chapter2.xhtml">Chapter Two</a></li>
+    <li><a href="chapter3.xhtml">Chapter Three</a></li>
+  </ol>
+</nav>
diff --git a/fixtures/toc-role-aria/meta.json b/fixtures/toc-role-aria/meta.json
new file mode 100644
index 0000000..4271ce6
--- /dev/null
+++ b/fixtures/toc-role-aria/meta.json
@@ -0,0 +1,12 @@
+{
+  "id": "toc-role-aria",
+  "description": "A table-of-contents navigation list, containing links to sectional headings, via explicit ARIA role",
+  "role": "toc",
+  "rolesCovered": [
+    "toc",
+    "list",
+    "listItem"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/toc-role-aria/utterances.json b/fixtures/toc-role-aria/utterances.json
new file mode 100644
index 0000000..492da85
--- /dev/null
+++ b/fixtures/toc-role-aria/utterances.json
@@ -0,0 +1,11 @@
+[
+  {
+    "text": "Chapter One"
+  },
+  {
+    "text": "Chapter Two"
+  },
+  {
+    "text": "Chapter Three"
+  }
+]
diff --git a/fixtures/video-html-native/gnd.json b/fixtures/video-html-native/gnd.json
new file mode 100644
index 0000000..170af44
--- /dev/null
+++ b/fixtures/video-html-native/gnd.json
@@ -0,0 +1,7 @@
+{
+  "role": [
+    "video"
+  ],
+  "videoref": "lamp-mechanism.mp4",
+  "description": "The lamp mechanism rotating at dusk"
+}
diff --git a/fixtures/video-html-native/input.html b/fixtures/video-html-native/input.html
new file mode 100644
index 0000000..74fe1fd
--- /dev/null
+++ b/fixtures/video-html-native/input.html
@@ -0,0 +1 @@
+<video src="lamp-mechanism.mp4" controls aria-label="The lamp mechanism rotating at dusk"></video>
diff --git a/fixtures/video-html-native/meta.json b/fixtures/video-html-native/meta.json
new file mode 100644
index 0000000..e781863
--- /dev/null
+++ b/fixtures/video-html-native/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "video-html-native",
+  "description": "video role via native <video src> element, with an aria-label as the accessible description",
+  "role": "video",
+  "rolesCovered": [
+    "video"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/video-html-native/utterances.json b/fixtures/video-html-native/utterances.json
new file mode 100644
index 0000000..401af4a
--- /dev/null
+++ b/fixtures/video-html-native/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "The lamp mechanism rotating at dusk"
+  }
+]
diff --git a/package-lock.json b/package-lock.json
index 079ef74..7179864 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,12 +1,12 @@
 {
   "name": "@readium/speech",
-  "version": "0.1.0",
+  "version": "0.1.1",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "@readium/speech",
-      "version": "0.1.0",
+      "version": "0.1.1",
       "license": "BSD-3-Clause",
       "dependencies": {
         "string-strip-html": "^13.4.23"
@@ -15,6 +15,7 @@
         "@ava/typescript": "^6.0.0",
         "ava": "^6.4.0",
         "http-server": "^14.1.1",
+        "linkedom": "^0.18.13",
         "rimraf": "^6.0.1",
         "ts-node": "^10.9.2",
         "typescript": "^5.8.3",
@@ -1878,6 +1879,20 @@
       "dev": true,
       "license": "MIT"
     },
+    "node_modules/boolbase": {
+      "version": "2.0.0",
+      "resolved": "https://registry.npmjs.org/boolbase/-/boolbase-2.0.0.tgz",
+      "integrity": "sha512-DkVaaQHymRhpYEYo9x1oo7Q7B0Y6KJUsjm3c9eTyFDby4MHLBTwZ6ZDWBel5zrYxj1WsZgC5oLpiz+93MluXeA==",
+      "dev": true,
+      "license": "ISC",
+      "engines": {
+        "node": ">=20.19.0"
+      },
+      "funding": {
+        "type": "github",
+        "url": "https://github.com/sponsors/fb55"
+      }
+    },
     "node_modules/brace-expansion": {
       "version": "2.0.2",
       "resolved": "https://registry.npmjs.org/brace-expansion/-/brace-expansion-2.0.2.tgz",
@@ -2270,6 +2285,48 @@
         "node": ">= 8"
       }
     },
+    "node_modules/css-select": {
+      "version": "7.0.0",
+      "resolved": "https://registry.npmjs.org/css-select/-/css-select-7.0.0.tgz",
+      "integrity": "sha512-snmjEVXy+1LnwXdxhYvTMj1d9tOh4HxkA1YmoayVBeeyR2C14Pum7fcxJIm4SswYspVy866eYNwlH6xC3/VH5g==",
+      "dev": true,
+      "license": "BSD-2-Clause",
+      "dependencies": {
+        "boolbase": "^2.0.0",
+        "css-what": "^8.0.0",
+        "domhandler": "^6.0.1",
+        "domutils": "^4.0.2",
+        "nth-check": "^3.0.1"
+      },
+      "engines": {
+        "node": ">=20.19.0"
+      },
+      "funding": {
+        "type": "github",
+        "url": "https://github.com/sponsors/fb55"
+      }
+    },
+    "node_modules/css-what": {
+      "version": "8.0.0",
+      "resolved": "https://registry.npmjs.org/css-what/-/css-what-8.0.0.tgz",
+      "integrity": "sha512-DH0Bqq3DNp5tdOReuNyAA+Ev4Y2GS5FMbZpeTLP6C4CDi0h5nL0BmUPChXw3o/qbHLDWHl49sbNqQVY7bMSDdw==",
+      "dev": true,
+      "license": "BSD-2-Clause",
+      "engines": {
+        "node": ">=20.19.0"
+      },
+      "funding": {
+        "type": "github",
+        "url": "https://github.com/sponsors/fb55"
+      }
+    },
+    "node_modules/cssom": {
+      "version": "0.5.0",
+      "resolved": "https://registry.npmjs.org/cssom/-/cssom-0.5.0.tgz",
+      "integrity": "sha512-iKuQcq+NdHqlAcwUY0o/HL69XQrUaQdMjmStJ8JFmUaiiQErlhrmuigkg/CU4E2J0IyUKUrMAgl36TvN67MqTw==",
+      "dev": true,
+      "license": "MIT"
+    },
     "node_modules/currently-unhandled": {
       "version": "0.4.1",
       "resolved": "https://registry.npmjs.org/currently-unhandled/-/currently-unhandled-0.4.1.tgz",
@@ -2341,6 +2398,90 @@
         "node": ">=0.3.1"
       }
     },
+    "node_modules/dom-serializer": {
+      "version": "3.1.1",
+      "resolved": "https://registry.npmjs.org/dom-serializer/-/dom-serializer-3.1.1.tgz",
+      "integrity": "sha512-4MEa38/QexBob6gFNwu+EGdWvhJ1OKuNwdYY3Y3NyeWDQfnGeDYQUDfIRzWu5B5gsv03so2Uxd28YC6zrsx3Lw==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "domelementtype": "^3.0.0",
+        "domhandler": "^6.0.0",
+        "entities": "^8.0.0"
+      },
+      "engines": {
+        "node": ">=20.19.0"
+      },
+      "funding": {
+        "type": "github",
+        "url": "https://github.com/cheeriojs/dom-serializer?sponsor=1"
+      }
+    },
+    "node_modules/dom-serializer/node_modules/entities": {
+      "version": "8.0.0",
+      "resolved": "https://registry.npmjs.org/entities/-/entities-8.0.0.tgz",
+      "integrity": "sha512-zwfzJecQ/Uej6tusMqwAqU/6KL2XaB2VZ2Jg54Je6ahNBGNH6Ek6g3jjNCF0fG9EWQKGZNddNjU5F1ZQn/sBnA==",
+      "dev": true,
+      "license": "BSD-2-Clause",
+      "engines": {
+        "node": ">=20.19.0"
+      },
+      "funding": {
+        "url": "https://github.com/fb55/entities?sponsor=1"
+      }
+    },
+    "node_modules/domelementtype": {
+      "version": "3.0.0",
+      "resolved": "https://registry.npmjs.org/domelementtype/-/domelementtype-3.0.0.tgz",
+      "integrity": "sha512-umCQid3jKbDmVjx8jGaW7uUykm4DEUeyV21hPxNMo2nV955DhUThwqyOIDtreepP31hl84X7G5U9ZfsWvIB3Pg==",
+      "dev": true,
+      "funding": [
+        {
+          "type": "github",
+          "url": "https://github.com/sponsors/fb55"
+        }
+      ],
+      "license": "BSD-2-Clause",
+      "engines": {
+        "node": ">=20.19.0"
+      }
+    },
+    "node_modules/domhandler": {
+      "version": "6.0.1",
+      "resolved": "https://registry.npmjs.org/domhandler/-/domhandler-6.0.1.tgz",
+      "integrity": "sha512-gYzvtM72ZtxQO0T048kd6HWSbbGCNOUwcnfQ01cqIJ4X2IYKFFHZ5mKvrQETcFXxsRObZulDaKmy//R7TPtsBg==",
+      "dev": true,
+      "license": "BSD-2-Clause",
+      "dependencies": {
+        "domelementtype": "^3.0.0"
+      },
+      "engines": {
+        "node": ">=20.19.0"
+      },
+      "funding": {
+        "type": "github",
+        "url": "https://github.com/fb55/domhandler?sponsor=1"
+      }
+    },
+    "node_modules/domutils": {
+      "version": "4.0.2",
+      "resolved": "https://registry.npmjs.org/domutils/-/domutils-4.0.2.tgz",
+      "integrity": "sha512-qI4JLRKnSzqFqr7hAlS5xQDusBCjKSEG4t4+7aNrIQMHBcsC2TGEhuyABJdYkgSewL57PNLYEiibY2iPKhKpaA==",
+      "dev": true,
+      "license": "BSD-2-Clause",
+      "dependencies": {
+        "dom-serializer": "^3.0.0",
+        "domelementtype": "^3.0.0",
+        "domhandler": "^6.0.0"
+      },
+      "engines": {
+        "node": ">=20.19.0"
+      },
+      "funding": {
+        "type": "github",
+        "url": "https://github.com/fb55/domutils?sponsor=1"
+      }
+    },
     "node_modules/dunder-proto": {
       "version": "1.0.1",
       "resolved": "https://registry.npmjs.org/dunder-proto/-/dunder-proto-1.0.1.tgz",
@@ -2384,9 +2525,9 @@
       "license": "MIT"
     },
     "node_modules/entities": {
-      "version": "7.0.0",
-      "resolved": "https://registry.npmjs.org/entities/-/entities-7.0.0.tgz",
-      "integrity": "sha512-FDWG5cmEYf2Z00IkYRhbFrwIwvdFKH07uV8dvNy0omp/Qb1xcyCWp2UDtcwJF4QZZvk0sLudP6/hAu42TaqVhQ==",
+      "version": "7.0.1",
+      "resolved": "https://registry.npmjs.org/entities/-/entities-7.0.1.tgz",
+      "integrity": "sha512-TWrgLOFUQTH994YUyl1yT4uyavY5nNB5muff+RtWaqNVCAK408b5ZnnbNAUEWLTCpum9w6arT70i1XdQ4UeOPA==",
       "dev": true,
       "license": "BSD-2-Clause",
       "engines": {
@@ -2994,6 +3135,105 @@
       ],
       "license": "MIT"
     },
+    "node_modules/html-escaper": {
+      "version": "3.0.3",
+      "resolved": "https://registry.npmjs.org/html-escaper/-/html-escaper-3.0.3.tgz",
+      "integrity": "sha512-RuMffC89BOWQoY0WKGpIhn5gX3iI54O6nRA0yC124NYVtzjmFWBIiFd8M0x+ZdX0P9R4lADg1mgP8C7PxGOWuQ==",
+      "dev": true,
+      "license": "MIT"
+    },
+    "node_modules/htmlparser2": {
+      "version": "10.1.0",
+      "resolved": "https://registry.npmjs.org/htmlparser2/-/htmlparser2-10.1.0.tgz",
+      "integrity": "sha512-VTZkM9GWRAtEpveh7MSF6SjjrpNVNNVJfFup7xTY3UpFtm67foy9HDVXneLtFVt4pMz5kZtgNcvCniNFb1hlEQ==",
+      "dev": true,
+      "funding": [
+        "https://github.com/fb55/htmlparser2?sponsor=1",
+        {
+          "type": "github",
+          "url": "https://github.com/sponsors/fb55"
+        }
+      ],
+      "license": "MIT",
+      "dependencies": {
+        "domelementtype": "^2.3.0",
+        "domhandler": "^5.0.3",
+        "domutils": "^3.2.2",
+        "entities": "^7.0.1"
+      }
+    },
+    "node_modules/htmlparser2/node_modules/dom-serializer": {
+      "version": "2.0.0",
+      "resolved": "https://registry.npmjs.org/dom-serializer/-/dom-serializer-2.0.0.tgz",
+      "integrity": "sha512-wIkAryiqt/nV5EQKqQpo3SToSOV9J0DnbJqwK7Wv/Trc92zIAYZ4FlMu+JPFW1DfGFt81ZTCGgDEabffXeLyJg==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "domelementtype": "^2.3.0",
+        "domhandler": "^5.0.2",
+        "entities": "^4.2.0"
+      },
+      "funding": {
+        "url": "https://github.com/cheeriojs/dom-serializer?sponsor=1"
+      }
+    },
+    "node_modules/htmlparser2/node_modules/dom-serializer/node_modules/entities": {
+      "version": "4.5.0",
+      "resolved": "https://registry.npmjs.org/entities/-/entities-4.5.0.tgz",
+      "integrity": "sha512-V0hjH4dGPh9Ao5p0MoRY6BVqtwCjhz6vI5LT8AJ55H+4g9/4vbHx1I54fS0XuclLhDHArPQCiMjDxjaL8fPxhw==",
+      "dev": true,
+      "license": "BSD-2-Clause",
+      "engines": {
+        "node": ">=0.12"
+      },
+      "funding": {
+        "url": "https://github.com/fb55/entities?sponsor=1"
+      }
+    },
+    "node_modules/htmlparser2/node_modules/domelementtype": {
+      "version": "2.3.0",
+      "resolved": "https://registry.npmjs.org/domelementtype/-/domelementtype-2.3.0.tgz",
+      "integrity": "sha512-OLETBj6w0OsagBwdXnPdN0cnMfF9opN69co+7ZrbfPGrdpPVNBUj02spi6B1N7wChLQiPn4CSH/zJvXw56gmHw==",
+      "dev": true,
+      "funding": [
+        {
+          "type": "github",
+          "url": "https://github.com/sponsors/fb55"
+        }
+      ],
+      "license": "BSD-2-Clause"
+    },
+    "node_modules/htmlparser2/node_modules/domhandler": {
+      "version": "5.0.3",
+      "resolved": "https://registry.npmjs.org/domhandler/-/domhandler-5.0.3.tgz",
+      "integrity": "sha512-cgwlv/1iFQiFnU96XXgROh8xTeetsnJiDsTc7TYCLFd9+/WNkIqPTxiM/8pSd8VIrhXGTf1Ny1q1hquVqDJB5w==",
+      "dev": true,
+      "license": "BSD-2-Clause",
+      "dependencies": {
+        "domelementtype": "^2.3.0"
+      },
+      "engines": {
+        "node": ">= 4"
+      },
+      "funding": {
+        "url": "https://github.com/fb55/domhandler?sponsor=1"
+      }
+    },
+    "node_modules/htmlparser2/node_modules/domutils": {
+      "version": "3.2.2",
+      "resolved": "https://registry.npmjs.org/domutils/-/domutils-3.2.2.tgz",
+      "integrity": "sha512-6kZKyUajlDuqlHKVX1w7gyslj9MPIXzIFiz/rGu35uC1wMi+kMhQwGhl4lt9unC9Vb9INnY9Z3/ZA3+FhASLaw==",
+      "dev": true,
+      "license": "BSD-2-Clause",
+      "dependencies": {
+        "dom-serializer": "^2.0.0",
+        "domelementtype": "^2.3.0",
+        "domhandler": "^5.0.3"
+      },
+      "funding": {
+        "url": "https://github.com/fb55/domutils?sponsor=1"
+      }
+    },
     "node_modules/http-proxy": {
       "version": "1.18.1",
       "resolved": "https://registry.npmjs.org/http-proxy/-/http-proxy-1.18.1.tgz",
@@ -3382,6 +3622,31 @@
       "dev": true,
       "license": "MIT"
     },
+    "node_modules/linkedom": {
+      "version": "0.18.13",
+      "resolved": "https://registry.npmjs.org/linkedom/-/linkedom-0.18.13.tgz",
+      "integrity": "sha512-ES/o9qotMpzpN2MHs+Iq/JcVoOj8Fa5wiQYrTdFpvAnwXL0g66XHHUc9WUMk6nAlBtGsFQ24ne+SYnvnaQ2FSw==",
+      "dev": true,
+      "license": "ISC",
+      "dependencies": {
+        "css-select": "^7.0.0",
+        "cssom": "^0.5.0",
+        "html-escaper": "^3.0.3",
+        "htmlparser2": "^10.1.0",
+        "uhyphen": "^0.2.0"
+      },
+      "engines": {
+        "node": ">=16"
+      },
+      "peerDependencies": {
+        "canvas": ">= 2"
+      },
+      "peerDependenciesMeta": {
+        "canvas": {
+          "optional": true
+        }
+      }
+    },
     "node_modules/load-json-file": {
       "version": "7.0.1",
       "resolved": "https://registry.npmjs.org/load-json-file/-/load-json-file-7.0.1.tgz",
@@ -3771,6 +4036,23 @@
         "url": "https://github.com/sponsors/sindresorhus"
       }
     },
+    "node_modules/nth-check": {
+      "version": "3.0.1",
+      "resolved": "https://registry.npmjs.org/nth-check/-/nth-check-3.0.1.tgz",
+      "integrity": "sha512-GX0gsdbGVCgnRgbeGaubfjpBXyYRWOOCVeYh08bSQvDZqxz5ndXs1OTfAt/h36G1xvI94YIspsI0sVFqAV9+RQ==",
+      "dev": true,
+      "license": "BSD-2-Clause",
+      "dependencies": {
+        "boolbase": "^2.0.0"
+      },
+      "engines": {
+        "node": ">=20.19.0"
+      },
+      "funding": {
+        "type": "github",
+        "url": "https://github.com/fb55/nth-check?sponsor=1"
+      }
+    },
     "node_modules/object-inspect": {
       "version": "1.13.4",
       "resolved": "https://registry.npmjs.org/object-inspect/-/object-inspect-1.13.4.tgz",
@@ -5008,6 +5290,13 @@
       "dev": true,
       "license": "MIT"
     },
+    "node_modules/uhyphen": {
+      "version": "0.2.0",
+      "resolved": "https://registry.npmjs.org/uhyphen/-/uhyphen-0.2.0.tgz",
+      "integrity": "sha512-qz3o9CHXmJJPGBdqzab7qAYuW8kQGKNEuoHFYrBwV6hWIMcpAmxDLXojcHfFr9US1Pe6zUswEIJIbLI610fuqA==",
+      "dev": true,
+      "license": "ISC"
+    },
     "node_modules/undici-types": {
       "version": "7.16.0",
       "resolved": "https://registry.npmjs.org/undici-types/-/undici-types-7.16.0.tgz",
diff --git a/package.json b/package.json
index 27f863e..728e6fd 100644
--- a/package.json
+++ b/package.json
@@ -4,11 +4,11 @@
   "description": "A TypeScript library for implementing read aloud features with Web technologies, following best practices for digital publishing.",
   "author": "Readium Foundation",
   "keywords": [
-    "readium", 
-    "speech", 
-    "tts", 
-    "text-to-speech", 
-    "read-aloud", 
+    "readium",
+    "speech",
+    "tts",
+    "text-to-speech",
+    "read-aloud",
     "accessibility"
   ],
   "homepage": "https://readium.org/speech/",
@@ -38,6 +38,7 @@
   "scripts": {
     "test": "npm run build && NODE_NO_WARNINGS=1 ava test/**/*.test.ts",
     "generate-metadata": "node scripts/generate-metadata.js",
+    "generate-fixtures-manifest": "node scripts/build-fixtures-manifest.js",
     "clean": "rimraf ./build",
     "build": "vite build",
     "start": "http-server ./",
@@ -47,6 +48,7 @@
     "@ava/typescript": "^6.0.0",
     "ava": "^6.4.0",
     "http-server": "^14.1.1",
+    "linkedom": "^0.18.13",
     "rimraf": "^6.0.1",
     "ts-node": "^10.9.2",
     "typescript": "^5.8.3",
diff --git a/scripts/build-fixtures-manifest.js b/scripts/build-fixtures-manifest.js
new file mode 100644
index 0000000..1f8fff1
--- /dev/null
+++ b/scripts/build-fixtures-manifest.js
@@ -0,0 +1,85 @@
+import fs from "fs";
+import path from "path";
+import { fileURLToPath } from "url";
+
+const __filename = fileURLToPath(import.meta.url);
+const __dirname = path.dirname(__filename);
+
+const FIXTURES_DIR = path.join(__dirname, "../fixtures");
+const MANIFEST_FILE = path.join(FIXTURES_DIR, "manifest.json");
+const COVERAGE_FILE = path.join(FIXTURES_DIR, "ROLES_COVERAGE.md");
+
+// The filesystem is the source of truth: every subdirectory of fixtures/
+// with a meta.json is a fixture. This script is the only thing that should
+// ever write manifest.json or ROLES_COVERAGE.md — never hand-edit them.
+
+const fixtureIds = fs
+  .readdirSync(FIXTURES_DIR, { withFileTypes: true })
+  .filter((entry) => entry.isDirectory())
+  .map((entry) => entry.name)
+  .filter((id) => fs.existsSync(path.join(FIXTURES_DIR, id, "meta.json")))
+  .sort();
+
+const manifest = fixtureIds.map((id) => {
+  const dir = path.join(FIXTURES_DIR, id);
+  const meta = JSON.parse(fs.readFileSync(path.join(dir, "meta.json"), "utf-8"));
+
+  for (const file of ["input.html", "gnd.json", "utterances.json"]) {
+    if (!fs.existsSync(path.join(dir, file))) {
+      throw new Error(`fixtures/${id} is missing ${file}`);
+    }
+  }
+  if (meta.id !== id) {
+    throw new Error(`fixtures/${id}/meta.json has id "${meta.id}", expected "${id}"`);
+  }
+
+  return {
+    id,
+    dir: id,
+    role: meta.role,
+    description: meta.description,
+    files: {
+      input: "input.html",
+      gnd: "gnd.json",
+      utterances: "utterances.json",
+    },
+  };
+});
+
+const ids = manifest.map((e) => e.id);
+const duplicates = ids.filter((id, i) => ids.indexOf(id) !== i);
+if (duplicates.length > 0) {
+  throw new Error(`duplicate fixture ids: ${[...new Set(duplicates)].join(", ")}`);
+}
+
+fs.writeFileSync(MANIFEST_FILE, JSON.stringify(manifest, null, 2) + "\n");
+
+// Flat "what exists" list, grouped only by role — not by any external
+// document's structure. This is not a checklist against roles.md; roles.md
+// was only ever the seed used to originally populate this suite.
+const byRole = new Map();
+for (const entry of manifest) {
+  if (!byRole.has(entry.role)) byRole.set(entry.role, []);
+  byRole.get(entry.role).push(entry);
+}
+
+let coverage = `# Fixture Coverage
+
+Every role currently covered by a fixture in this directory, generated from
+\`fixtures/*/meta.json\` by \`scripts/build-fixtures-manifest.js\` — do not
+hand-edit this file. Run \`npm run generate-fixtures-manifest\` after adding,
+renaming, or removing a fixture.
+
+| Role | Fixtures |
+| --- | --- |
+`;
+
+for (const [role, entries] of [...byRole.entries()].sort((a, b) => a[0].localeCompare(b[0]))) {
+  coverage += `| \`${role}\` | ${entries.map((e) => `\`${e.id}\``).join(", ")} |\n`;
+}
+
+coverage += `\n${manifest.length} fixtures across ${byRole.size} roles.\n`;
+
+fs.writeFileSync(COVERAGE_FILE, coverage);
+
+console.log(`Wrote manifest.json (${manifest.length} fixtures) and ROLES_COVERAGE.md (${byRole.size} roles).`);
diff --git a/src/gnd/index.ts b/src/gnd/index.ts
new file mode 100644
index 0000000..9047e87
--- /dev/null
+++ b/src/gnd/index.ts
@@ -0,0 +1 @@
+export type { GndRole, GndTextAlternative, GndNode, GndDocument } from "./types.js";
diff --git a/src/gnd/types.ts b/src/gnd/types.ts
new file mode 100644
index 0000000..149c71b
--- /dev/null
+++ b/src/gnd/types.ts
@@ -0,0 +1,36 @@
+// Guided Navigation document model.
+//
+// This is a minimal, intentionally loose type stub for the fixture suite in
+// `fixtures/` to type-check against. It does not implement HTML parsing or
+// utterance extraction — see fixtures/README.md for the fixture format this
+// is meant to satisfy.
+//
+// The upstream spec is still evolving: https://github.com/readium/guided-navigation
+
+// See roles.md for the full, growing vocabulary — kept as a plain string
+// rather than a union so new roles don't require a type change here.
+export type GndRole = string;
+
+export interface GndTextAlternative {
+  language: string;
+  plain?: string;
+  ssml?: string;
+}
+
+export interface GndNode {
+  role?: GndRole[];
+  text?: string | GndTextAlternative;
+  description?: string;
+  imgref?: string;
+  audioref?: string;
+  videoref?: string;
+  textref?: string;
+  id?: string;
+  lang?: string;
+  children?: GndNode[];
+}
+
+// TODO: root shape (single node vs. an implicit multi-node fragment) is not
+// yet settled upstream; fixtures with multiple top-level siblings currently
+// use a bare `{ children: GndNode[] }` with no role.
+export type GndDocument = GndNode;
diff --git a/test/gnd/fixtures.test.ts b/test/gnd/fixtures.test.ts
new file mode 100644
index 0000000..4a48d10
--- /dev/null
+++ b/test/gnd/fixtures.test.ts
@@ -0,0 +1,38 @@
+import test from "ava";
+import { loadManifest, loadFixture } from "../testUtils.js";
+
+const manifest = loadManifest();
+
+test("manifest is a non-empty array", (t) => {
+  t.true(Array.isArray(manifest));
+  t.true(manifest.length > 0);
+});
+
+test("manifest has no duplicate ids", (t) => {
+  const ids = manifest.map((entry) => entry.id);
+  t.is(new Set(ids).size, ids.length);
+});
+
+for (const entry of manifest) {
+  test(`fixture "${entry.id}": loads and has the expected shape`, (t) => {
+    t.is(entry.dir, entry.id);
+
+    const fixture = loadFixture(entry.id);
+
+    t.is(fixture.meta.id, entry.id);
+    t.is(fixture.meta.role, entry.role);
+
+    t.true(fixture.inputHtml.trim().length > 0, "input.html must not be empty");
+
+    t.true(
+      typeof fixture.gnd === "object" && fixture.gnd !== null,
+      "gnd.json must parse to an object",
+    );
+
+    t.true(Array.isArray(fixture.utterances), "utterances.json must parse to an array");
+    for (const utterance of fixture.utterances as Record<string, unknown>[]) {
+      t.true(typeof utterance === "object" && utterance !== null);
+      t.true(typeof utterance.text === "string", "each utterance needs a text field");
+    }
+  });
+}
diff --git a/test/testUtils.ts b/test/testUtils.ts
index 594880e..277788f 100644
--- a/test/testUtils.ts
+++ b/test/testUtils.ts
@@ -14,3 +14,52 @@ export function getDefaultRegion(language: string): string {
   const langData = JSON.parse(readFileSync(jsonPath, "utf-8"));
   return langData.defaultRegion;
 }
+
+export interface FixtureManifestEntry {
+  id: string;
+  dir: string;
+  role: string;
+  description: string;
+  files: {
+    input: string;
+    gnd: string;
+    utterances: string;
+  };
+}
+
+export interface FixtureMeta {
+  id: string;
+  description: string;
+  role: string;
+  rolesCovered: string[];
+  sourceRef: string;
+  inputKind: "fragment" | "document";
+}
+
+export interface LoadedFixture {
+  meta: FixtureMeta;
+  inputHtml: string;
+  gnd: unknown;
+  utterances: unknown[];
+}
+
+const fixturesDir = join(__dirname, "../fixtures");
+
+/**
+ * Test-only helper to read fixtures/manifest.json
+ */
+export function loadManifest(): FixtureManifestEntry[] {
+  return JSON.parse(readFileSync(join(fixturesDir, "manifest.json"), "utf-8"));
+}
+
+/**
+ * Test-only helper to read every file of a fixture directory by id
+ */
+export function loadFixture(id: string): LoadedFixture {
+  const dir = join(fixturesDir, id);
+  const meta: FixtureMeta = JSON.parse(readFileSync(join(dir, "meta.json"), "utf-8"));
+  const inputHtml = readFileSync(join(dir, "input.html"), "utf-8");
+  const gnd = JSON.parse(readFileSync(join(dir, "gnd.json"), "utf-8"));
+  const utterances = JSON.parse(readFileSync(join(dir, "utterances.json"), "utf-8"));
+  return { meta, inputHtml, gnd, utterances };
+}

From 130d26088c0b31540eb79ccc13fdef0e4a13befe Mon Sep 17 00:00:00 2001
From: Jiminy Panoz <JayPanoz@users.noreply.github.com>
Date: Thu, 9 Jul 2026 14:05:59 +0200
Subject: [PATCH 2/7] Correct fixtures roles from Go-toolkit analysis

---
 fixtures/ROLES_COVERAGE.md                    |  6 ++-
 fixtures/appendix-epub-type/gnd.json          |  1 +
 fixtures/bibliography-epub-type/gnd.json      |  1 +
 fixtures/chapter-epub-type/gnd.json           |  1 +
 fixtures/chapter-role-aria/gnd.json           |  1 +
 fixtures/cover-epub-type/gnd.json             |  1 +
 fixtures/cover-role-aria/gnd.json             |  1 +
 fixtures/endnotes-epub-type/gnd.json          |  1 +
 fixtures/foreword-epub-type/gnd.json          |  6 +++
 fixtures/foreword-epub-type/input.html        | 11 +++++
 fixtures/foreword-epub-type/meta.json         | 10 ++++
 fixtures/foreword-epub-type/utterances.json   |  5 ++
 fixtures/foreword-role-aria/gnd.json          |  6 +++
 fixtures/foreword-role-aria/input.html        |  1 +
 fixtures/foreword-role-aria/meta.json         | 10 ++++
 fixtures/foreword-role-aria/utterances.json   |  5 ++
 fixtures/index-epub-type/gnd.json             |  1 +
 fixtures/landmarks-epub-type/gnd.json         |  1 +
 fixtures/loa-epub-type/gnd.json               |  1 +
 fixtures/loi-epub-type/gnd.json               |  1 +
 fixtures/lot-epub-type/gnd.json               |  1 +
 fixtures/lov-epub-type/gnd.json               |  1 +
 fixtures/manifest.json                        | 48 ++++++++++++++-----
 fixtures/pagelist-epub-type/gnd.json          |  1 +
 fixtures/pagelist-role-aria/gnd.json          |  1 +
 .../gnd.json                                  | 25 ----------
 .../input.html                                |  1 -
 .../meta.json                                 | 10 ----
 .../utterances.json                           | 14 ------
 fixtures/part-epub-type/gnd.json              |  1 +
 fixtures/part-role-aria/gnd.json              |  1 +
 fixtures/pullquote-epub-type/gnd.json         |  1 +
 fixtures/qna-epub-type/gnd.json               |  1 +
 fixtures/section-html-native/gnd.json         |  6 +++
 fixtures/section-html-native/input.html       |  1 +
 fixtures/section-html-native/meta.json        | 10 ++++
 fixtures/section-html-native/utterances.json  |  5 ++
 fixtures/table-html-native/gnd.json           |  4 +-
 fixtures/table-html-native/input.html         |  4 +-
 fixtures/table-html-native/meta.json          |  3 +-
 fixtures/table-role-aria/gnd.json             |  4 +-
 fixtures/table-role-aria/input.html           |  4 +-
 fixtures/table-role-aria/meta.json            |  3 +-
 fixtures/tip-epub-type/gnd.json               |  1 +
 fixtures/toc-epub-type/gnd.json               |  1 +
 fixtures/toc-role-aria/gnd.json               |  1 +
 46 files changed, 149 insertions(+), 75 deletions(-)
 create mode 100644 fixtures/foreword-epub-type/gnd.json
 create mode 100644 fixtures/foreword-epub-type/input.html
 create mode 100644 fixtures/foreword-epub-type/meta.json
 create mode 100644 fixtures/foreword-epub-type/utterances.json
 create mode 100644 fixtures/foreword-role-aria/gnd.json
 create mode 100644 fixtures/foreword-role-aria/input.html
 create mode 100644 fixtures/foreword-role-aria/meta.json
 create mode 100644 fixtures/foreword-role-aria/utterances.json
 delete mode 100644 fixtures/paragraph-multilingual-text-children/gnd.json
 delete mode 100644 fixtures/paragraph-multilingual-text-children/input.html
 delete mode 100644 fixtures/paragraph-multilingual-text-children/meta.json
 delete mode 100644 fixtures/paragraph-multilingual-text-children/utterances.json
 create mode 100644 fixtures/section-html-native/gnd.json
 create mode 100644 fixtures/section-html-native/input.html
 create mode 100644 fixtures/section-html-native/meta.json
 create mode 100644 fixtures/section-html-native/utterances.json

diff --git a/fixtures/ROLES_COVERAGE.md b/fixtures/ROLES_COVERAGE.md
index 68172b1..debe51c 100644
--- a/fixtures/ROLES_COVERAGE.md
+++ b/fixtures/ROLES_COVERAGE.md
@@ -36,6 +36,7 @@ renaming, or removing a fixture.
 | `example` | `example-epub-type`, `example-role-aria` |
 | `figure` | `figure-basic-epub-type`, `figure-basic-html-native`, `figure-basic-role-aria`, `figure-caption-html-native`, `figure-caption-role-aria`, `figure-describedby` |
 | `footnote` | `footnote-epub-type`, `footnote-role-aria` |
+| `foreword` | `foreword-epub-type`, `foreword-role-aria` |
 | `glossary` | `glossary-epub-type`, `glossary-role-aria` |
 | `glossref` | `glossref-epub-type`, `glossref-role-aria` |
 | `header` | `header-html-native` |
@@ -55,7 +56,7 @@ renaming, or removing a fixture.
 | `notice` | `notice-epub-type`, `notice-role-aria` |
 | `pagebreak` | `pagebreak-epub-type`, `pagebreak-role-aria` |
 | `pagelist` | `pagelist-epub-type`, `pagelist-role-aria` |
-| `paragraph` | `paragraph-basic`, `paragraph-multilingual-ssml-lang`, `paragraph-multilingual-text-children` |
+| `paragraph` | `paragraph-basic`, `paragraph-multilingual-ssml-lang` |
 | `part` | `part-epub-type`, `part-role-aria` |
 | `preface` | `preface-epub-type`, `preface-role-aria` |
 | `preformatted` | `preformatted-html-native` |
@@ -64,6 +65,7 @@ renaming, or removing a fixture.
 | `pullquote` | `pullquote-epub-type`, `pullquote-role-aria` |
 | `qna` | `qna-epub-type`, `qna-role-aria` |
 | `region` | `region-role-aria` |
+| `section` | `section-html-native` |
 | `separator` | `separator-html-native`, `separator-role-aria` |
 | `subtitle` | `subtitle-epub-type`, `subtitle-role-aria` |
 | `summary` | `summary-html-native` |
@@ -73,4 +75,4 @@ renaming, or removing a fixture.
 | `toc` | `toc-epub-type`, `toc-role-aria` |
 | `video` | `video-html-native` |
 
-121 fixtures across 65 roles.
+123 fixtures across 67 roles.
diff --git a/fixtures/appendix-epub-type/gnd.json b/fixtures/appendix-epub-type/gnd.json
index 4592a4a..a946bd6 100644
--- a/fixtures/appendix-epub-type/gnd.json
+++ b/fixtures/appendix-epub-type/gnd.json
@@ -1,5 +1,6 @@
 {
   "role": [
+    "section",
     "appendix"
   ],
   "text": "A table of lighthouse construction dates referenced in the text."
diff --git a/fixtures/bibliography-epub-type/gnd.json b/fixtures/bibliography-epub-type/gnd.json
index 8f58379..91f4f6a 100644
--- a/fixtures/bibliography-epub-type/gnd.json
+++ b/fixtures/bibliography-epub-type/gnd.json
@@ -1,5 +1,6 @@
 {
   "role": [
+    "section",
     "bibliography"
   ],
   "children": [
diff --git a/fixtures/chapter-epub-type/gnd.json b/fixtures/chapter-epub-type/gnd.json
index 9e95612..137ad53 100644
--- a/fixtures/chapter-epub-type/gnd.json
+++ b/fixtures/chapter-epub-type/gnd.json
@@ -1,5 +1,6 @@
 {
   "role": [
+    "section",
     "chapter"
   ],
   "children": [
diff --git a/fixtures/chapter-role-aria/gnd.json b/fixtures/chapter-role-aria/gnd.json
index 9e95612..137ad53 100644
--- a/fixtures/chapter-role-aria/gnd.json
+++ b/fixtures/chapter-role-aria/gnd.json
@@ -1,5 +1,6 @@
 {
   "role": [
+    "section",
     "chapter"
   ],
   "children": [
diff --git a/fixtures/cover-epub-type/gnd.json b/fixtures/cover-epub-type/gnd.json
index 7ca55ac..76a839b 100644
--- a/fixtures/cover-epub-type/gnd.json
+++ b/fixtures/cover-epub-type/gnd.json
@@ -1,5 +1,6 @@
 {
   "role": [
+    "section",
     "cover"
   ],
   "children": [
diff --git a/fixtures/cover-role-aria/gnd.json b/fixtures/cover-role-aria/gnd.json
index c26f574..36c72e3 100644
--- a/fixtures/cover-role-aria/gnd.json
+++ b/fixtures/cover-role-aria/gnd.json
@@ -1,5 +1,6 @@
 {
   "role": [
+    "image",
     "cover"
   ],
   "imgref": "cover.jpg",
diff --git a/fixtures/endnotes-epub-type/gnd.json b/fixtures/endnotes-epub-type/gnd.json
index bbaa3b7..9a35128 100644
--- a/fixtures/endnotes-epub-type/gnd.json
+++ b/fixtures/endnotes-epub-type/gnd.json
@@ -1,5 +1,6 @@
 {
   "role": [
+    "section",
     "endnotes"
   ],
   "children": [
diff --git a/fixtures/foreword-epub-type/gnd.json b/fixtures/foreword-epub-type/gnd.json
new file mode 100644
index 0000000..1bee105
--- /dev/null
+++ b/fixtures/foreword-epub-type/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "foreword"
+  ],
+  "text": "A respected maritime historian introduces this account of the coastline's lighthouses."
+}
diff --git a/fixtures/foreword-epub-type/input.html b/fixtures/foreword-epub-type/input.html
new file mode 100644
index 0000000..a6d16a1
--- /dev/null
+++ b/fixtures/foreword-epub-type/input.html
@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:epub="http://www.idpf.org/2007/ops">
+<head>
+<meta charset="utf-8"/>
+<title>Fixture</title>
+</head>
+<body>
+<div epub:type="foreword">A respected maritime historian introduces this account of the coastline's lighthouses.</div>
+</body>
+</html>
diff --git a/fixtures/foreword-epub-type/meta.json b/fixtures/foreword-epub-type/meta.json
new file mode 100644
index 0000000..7d37cbc
--- /dev/null
+++ b/fixtures/foreword-epub-type/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "foreword-epub-type",
+  "description": "foreword role via epub:type=\"foreword\"",
+  "role": "foreword",
+  "rolesCovered": [
+    "foreword"
+  ],
+  "sourceRef": "https://www.w3.org/TR/epub-ssv-11/#sec-sections",
+  "inputKind": "document"
+}
diff --git a/fixtures/foreword-epub-type/utterances.json b/fixtures/foreword-epub-type/utterances.json
new file mode 100644
index 0000000..16ad612
--- /dev/null
+++ b/fixtures/foreword-epub-type/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "A respected maritime historian introduces this account of the coastline's lighthouses."
+  }
+]
diff --git a/fixtures/foreword-role-aria/gnd.json b/fixtures/foreword-role-aria/gnd.json
new file mode 100644
index 0000000..1bee105
--- /dev/null
+++ b/fixtures/foreword-role-aria/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "foreword"
+  ],
+  "text": "A respected maritime historian introduces this account of the coastline's lighthouses."
+}
diff --git a/fixtures/foreword-role-aria/input.html b/fixtures/foreword-role-aria/input.html
new file mode 100644
index 0000000..1880030
--- /dev/null
+++ b/fixtures/foreword-role-aria/input.html
@@ -0,0 +1 @@
+<div role="doc-foreword">A respected maritime historian introduces this account of the coastline's lighthouses.</div>
diff --git a/fixtures/foreword-role-aria/meta.json b/fixtures/foreword-role-aria/meta.json
new file mode 100644
index 0000000..e5340be
--- /dev/null
+++ b/fixtures/foreword-role-aria/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "foreword-role-aria",
+  "description": "foreword role via explicit ARIA role=\"doc-foreword\"",
+  "role": "foreword",
+  "rolesCovered": [
+    "foreword"
+  ],
+  "sourceRef": "https://www.w3.org/TR/dpub-aria-1.0/#doc-foreword",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/foreword-role-aria/utterances.json b/fixtures/foreword-role-aria/utterances.json
new file mode 100644
index 0000000..16ad612
--- /dev/null
+++ b/fixtures/foreword-role-aria/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "A respected maritime historian introduces this account of the coastline's lighthouses."
+  }
+]
diff --git a/fixtures/index-epub-type/gnd.json b/fixtures/index-epub-type/gnd.json
index 015cd04..cadfbaa 100644
--- a/fixtures/index-epub-type/gnd.json
+++ b/fixtures/index-epub-type/gnd.json
@@ -1,5 +1,6 @@
 {
   "role": [
+    "navigation",
     "index"
   ],
   "children": [
diff --git a/fixtures/landmarks-epub-type/gnd.json b/fixtures/landmarks-epub-type/gnd.json
index 21b65c3..5a70aab 100644
--- a/fixtures/landmarks-epub-type/gnd.json
+++ b/fixtures/landmarks-epub-type/gnd.json
@@ -1,5 +1,6 @@
 {
   "role": [
+    "navigation",
     "landmarks"
   ],
   "children": [
diff --git a/fixtures/loa-epub-type/gnd.json b/fixtures/loa-epub-type/gnd.json
index 3ca91fb..a15c98f 100644
--- a/fixtures/loa-epub-type/gnd.json
+++ b/fixtures/loa-epub-type/gnd.json
@@ -1,5 +1,6 @@
 {
   "role": [
+    "navigation",
     "loa"
   ],
   "children": [
diff --git a/fixtures/loi-epub-type/gnd.json b/fixtures/loi-epub-type/gnd.json
index 48ca728..c75c0f8 100644
--- a/fixtures/loi-epub-type/gnd.json
+++ b/fixtures/loi-epub-type/gnd.json
@@ -1,5 +1,6 @@
 {
   "role": [
+    "navigation",
     "loi"
   ],
   "children": [
diff --git a/fixtures/lot-epub-type/gnd.json b/fixtures/lot-epub-type/gnd.json
index 94898db..9737664 100644
--- a/fixtures/lot-epub-type/gnd.json
+++ b/fixtures/lot-epub-type/gnd.json
@@ -1,5 +1,6 @@
 {
   "role": [
+    "navigation",
     "lot"
   ],
   "children": [
diff --git a/fixtures/lov-epub-type/gnd.json b/fixtures/lov-epub-type/gnd.json
index 5456b84..2206a61 100644
--- a/fixtures/lov-epub-type/gnd.json
+++ b/fixtures/lov-epub-type/gnd.json
@@ -1,5 +1,6 @@
 {
   "role": [
+    "navigation",
     "lov"
   ],
   "children": [
diff --git a/fixtures/manifest.json b/fixtures/manifest.json
index 5f13f7c..d81437d 100644
--- a/fixtures/manifest.json
+++ b/fixtures/manifest.json
@@ -615,6 +615,28 @@
       "utterances": "utterances.json"
     }
   },
+  {
+    "id": "foreword-epub-type",
+    "dir": "foreword-epub-type",
+    "role": "foreword",
+    "description": "foreword role via epub:type=\"foreword\"",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "foreword-role-aria",
+    "dir": "foreword-role-aria",
+    "role": "foreword",
+    "description": "foreword role via explicit ARIA role=\"doc-foreword\"",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
   {
     "id": "glossary-epub-type",
     "dir": "glossary-epub-type",
@@ -1011,17 +1033,6 @@
       "utterances": "utterances.json"
     }
   },
-  {
-    "id": "paragraph-multilingual-text-children",
-    "dir": "paragraph-multilingual-text-children",
-    "role": "paragraph",
-    "description": "A paragraph with an inline foreign-language phrase, represented as separate text children per language",
-    "files": {
-      "input": "input.html",
-      "gnd": "gnd.json",
-      "utterances": "utterances.json"
-    }
-  },
   {
     "id": "part-epub-type",
     "dir": "part-epub-type",
@@ -1165,6 +1176,17 @@
       "utterances": "utterances.json"
     }
   },
+  {
+    "id": "section-html-native",
+    "dir": "section-html-native",
+    "role": "section",
+    "description": "section role via native <section> element with no more specific semantic",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
   {
     "id": "separator-html-native",
     "dir": "separator-html-native",
@@ -1224,7 +1246,7 @@
     "id": "table-html-native",
     "dir": "table-html-native",
     "role": "table",
-    "description": "A table with a header row, via native <table>/<tr>/<th>/<td>",
+    "description": "A table with a header row and row headers, via native <table>/<tr>/<th>/<td>",
     "files": {
       "input": "input.html",
       "gnd": "gnd.json",
@@ -1235,7 +1257,7 @@
     "id": "table-role-aria",
     "dir": "table-role-aria",
     "role": "table",
-    "description": "A table with a header row, via explicit ARIA table/row/columnheader/cell roles",
+    "description": "A table with a header row and row headers, via explicit ARIA table/row/columnheader/rowheader/cell roles",
     "files": {
       "input": "input.html",
       "gnd": "gnd.json",
diff --git a/fixtures/pagelist-epub-type/gnd.json b/fixtures/pagelist-epub-type/gnd.json
index bcc4f55..b16050a 100644
--- a/fixtures/pagelist-epub-type/gnd.json
+++ b/fixtures/pagelist-epub-type/gnd.json
@@ -1,5 +1,6 @@
 {
   "role": [
+    "navigation",
     "pagelist"
   ],
   "children": [
diff --git a/fixtures/pagelist-role-aria/gnd.json b/fixtures/pagelist-role-aria/gnd.json
index bcc4f55..b16050a 100644
--- a/fixtures/pagelist-role-aria/gnd.json
+++ b/fixtures/pagelist-role-aria/gnd.json
@@ -1,5 +1,6 @@
 {
   "role": [
+    "navigation",
     "pagelist"
   ],
   "children": [
diff --git a/fixtures/paragraph-multilingual-text-children/gnd.json b/fixtures/paragraph-multilingual-text-children/gnd.json
deleted file mode 100644
index 20a6282..0000000
--- a/fixtures/paragraph-multilingual-text-children/gnd.json
+++ /dev/null
@@ -1,25 +0,0 @@
-{
-  "role": [
-    "paragraph"
-  ],
-  "children": [
-    {
-      "text": {
-        "plain": "This job requires a certain",
-        "language": "en"
-      }
-    },
-    {
-      "text": {
-        "plain": "savoir faire",
-        "language": "fr"
-      }
-    },
-    {
-      "text": {
-        "plain": "that can only be acquired over time.",
-        "language": "en"
-      }
-    }
-  ]
-}
diff --git a/fixtures/paragraph-multilingual-text-children/input.html b/fixtures/paragraph-multilingual-text-children/input.html
deleted file mode 100644
index 83539a5..0000000
--- a/fixtures/paragraph-multilingual-text-children/input.html
+++ /dev/null
@@ -1 +0,0 @@
-<p>This job requires a certain <em xml:lang="fr">savoir faire</em> that can only be acquired over time.</p>
diff --git a/fixtures/paragraph-multilingual-text-children/meta.json b/fixtures/paragraph-multilingual-text-children/meta.json
deleted file mode 100644
index 29a7fc2..0000000
--- a/fixtures/paragraph-multilingual-text-children/meta.json
+++ /dev/null
@@ -1,10 +0,0 @@
-{
-  "id": "paragraph-multilingual-text-children",
-  "description": "A paragraph with an inline foreign-language phrase, represented as separate text children per language",
-  "role": "paragraph",
-  "rolesCovered": [
-    "paragraph"
-  ],
-  "sourceRef": "https://github.com/readium/guided-navigation/tree/main/examples/read-aloud#multilingual-text",
-  "inputKind": "fragment"
-}
diff --git a/fixtures/paragraph-multilingual-text-children/utterances.json b/fixtures/paragraph-multilingual-text-children/utterances.json
deleted file mode 100644
index bcaf0b6..0000000
--- a/fixtures/paragraph-multilingual-text-children/utterances.json
+++ /dev/null
@@ -1,14 +0,0 @@
-[
-  {
-    "text": "This job requires a certain",
-    "language": "en"
-  },
-  {
-    "text": "savoir faire",
-    "language": "fr"
-  },
-  {
-    "text": "that can only be acquired over time.",
-    "language": "en"
-  }
-]
diff --git a/fixtures/part-epub-type/gnd.json b/fixtures/part-epub-type/gnd.json
index 8a2259f..d7f29f2 100644
--- a/fixtures/part-epub-type/gnd.json
+++ b/fixtures/part-epub-type/gnd.json
@@ -1,5 +1,6 @@
 {
   "role": [
+    "section",
     "part"
   ],
   "children": [
diff --git a/fixtures/part-role-aria/gnd.json b/fixtures/part-role-aria/gnd.json
index 8a2259f..d7f29f2 100644
--- a/fixtures/part-role-aria/gnd.json
+++ b/fixtures/part-role-aria/gnd.json
@@ -1,5 +1,6 @@
 {
   "role": [
+    "section",
     "part"
   ],
   "children": [
diff --git a/fixtures/pullquote-epub-type/gnd.json b/fixtures/pullquote-epub-type/gnd.json
index d79532c..e6171ba 100644
--- a/fixtures/pullquote-epub-type/gnd.json
+++ b/fixtures/pullquote-epub-type/gnd.json
@@ -1,5 +1,6 @@
 {
   "role": [
+    "aside",
     "pullquote"
   ],
   "text": "The lamp still turns, though no one climbs the stairs anymore."
diff --git a/fixtures/qna-epub-type/gnd.json b/fixtures/qna-epub-type/gnd.json
index e22b599..6d27744 100644
--- a/fixtures/qna-epub-type/gnd.json
+++ b/fixtures/qna-epub-type/gnd.json
@@ -1,5 +1,6 @@
 {
   "role": [
+    "section",
     "qna"
   ],
   "text": "Q: How often was the lamp refueled? A: Nightly, by hand."
diff --git a/fixtures/section-html-native/gnd.json b/fixtures/section-html-native/gnd.json
new file mode 100644
index 0000000..e90d762
--- /dev/null
+++ b/fixtures/section-html-native/gnd.json
@@ -0,0 +1,6 @@
+{
+  "role": [
+    "section"
+  ],
+  "text": "The lighthouse was decommissioned in 1998, though its light still functions as a private aid to navigation."
+}
diff --git a/fixtures/section-html-native/input.html b/fixtures/section-html-native/input.html
new file mode 100644
index 0000000..50b865c
--- /dev/null
+++ b/fixtures/section-html-native/input.html
@@ -0,0 +1 @@
+<section>The lighthouse was decommissioned in 1998, though its light still functions as a private aid to navigation.</section>
diff --git a/fixtures/section-html-native/meta.json b/fixtures/section-html-native/meta.json
new file mode 100644
index 0000000..e58c599
--- /dev/null
+++ b/fixtures/section-html-native/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "section-html-native",
+  "description": "section role via native <section> element with no more specific semantic",
+  "role": "section",
+  "rolesCovered": [
+    "section"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/section-html-native/utterances.json b/fixtures/section-html-native/utterances.json
new file mode 100644
index 0000000..0842118
--- /dev/null
+++ b/fixtures/section-html-native/utterances.json
@@ -0,0 +1,5 @@
+[
+  {
+    "text": "The lighthouse was decommissioned in 1998, though its light still functions as a private aid to navigation."
+  }
+]
diff --git a/fixtures/table-html-native/gnd.json b/fixtures/table-html-native/gnd.json
index ec9b8e6..e69c493 100644
--- a/fixtures/table-html-native/gnd.json
+++ b/fixtures/table-html-native/gnd.json
@@ -29,7 +29,7 @@
       "children": [
         {
           "role": [
-            "cell"
+            "rowheader"
           ],
           "text": "Ada"
         },
@@ -48,7 +48,7 @@
       "children": [
         {
           "role": [
-            "cell"
+            "rowheader"
           ],
           "text": "Grace"
         },
diff --git a/fixtures/table-html-native/input.html b/fixtures/table-html-native/input.html
index af33a76..e16e3d3 100644
--- a/fixtures/table-html-native/input.html
+++ b/fixtures/table-html-native/input.html
@@ -1,5 +1,5 @@
 <table>
   <tr><th scope="col">Name</th><th scope="col">Role</th></tr>
-  <tr><td>Ada</td><td>Engineer</td></tr>
-  <tr><td>Grace</td><td>Admiral</td></tr>
+  <tr><th scope="row">Ada</th><td>Engineer</td></tr>
+  <tr><th scope="row">Grace</th><td>Admiral</td></tr>
 </table>
diff --git a/fixtures/table-html-native/meta.json b/fixtures/table-html-native/meta.json
index b2593c5..9d6a7cf 100644
--- a/fixtures/table-html-native/meta.json
+++ b/fixtures/table-html-native/meta.json
@@ -1,11 +1,12 @@
 {
   "id": "table-html-native",
-  "description": "A table with a header row, via native <table>/<tr>/<th>/<td>",
+  "description": "A table with a header row and row headers, via native <table>/<tr>/<th>/<td>",
   "role": "table",
   "rolesCovered": [
     "table",
     "row",
     "columnheader",
+    "rowheader",
     "cell"
   ],
   "sourceRef": "https://github.com/readium/guided-navigation/tree/main/examples/read-aloud",
diff --git a/fixtures/table-role-aria/gnd.json b/fixtures/table-role-aria/gnd.json
index ec9b8e6..e69c493 100644
--- a/fixtures/table-role-aria/gnd.json
+++ b/fixtures/table-role-aria/gnd.json
@@ -29,7 +29,7 @@
       "children": [
         {
           "role": [
-            "cell"
+            "rowheader"
           ],
           "text": "Ada"
         },
@@ -48,7 +48,7 @@
       "children": [
         {
           "role": [
-            "cell"
+            "rowheader"
           ],
           "text": "Grace"
         },
diff --git a/fixtures/table-role-aria/input.html b/fixtures/table-role-aria/input.html
index ada669e..c9e3ed2 100644
--- a/fixtures/table-role-aria/input.html
+++ b/fixtures/table-role-aria/input.html
@@ -1,5 +1,5 @@
 <div role="table">
   <div role="row"><div role="columnheader">Name</div><div role="columnheader">Role</div></div>
-  <div role="row"><div role="cell">Ada</div><div role="cell">Engineer</div></div>
-  <div role="row"><div role="cell">Grace</div><div role="cell">Admiral</div></div>
+  <div role="row"><div role="rowheader">Ada</div><div role="cell">Engineer</div></div>
+  <div role="row"><div role="rowheader">Grace</div><div role="cell">Admiral</div></div>
 </div>
diff --git a/fixtures/table-role-aria/meta.json b/fixtures/table-role-aria/meta.json
index 8723961..8c1aac7 100644
--- a/fixtures/table-role-aria/meta.json
+++ b/fixtures/table-role-aria/meta.json
@@ -1,11 +1,12 @@
 {
   "id": "table-role-aria",
-  "description": "A table with a header row, via explicit ARIA table/row/columnheader/cell roles",
+  "description": "A table with a header row and row headers, via explicit ARIA table/row/columnheader/rowheader/cell roles",
   "role": "table",
   "rolesCovered": [
     "table",
     "row",
     "columnheader",
+    "rowheader",
     "cell"
   ],
   "sourceRef": "https://github.com/readium/guided-navigation/tree/main/examples/read-aloud",
diff --git a/fixtures/tip-epub-type/gnd.json b/fixtures/tip-epub-type/gnd.json
index 703f951..0d5d353 100644
--- a/fixtures/tip-epub-type/gnd.json
+++ b/fixtures/tip-epub-type/gnd.json
@@ -1,5 +1,6 @@
 {
   "role": [
+    "aside",
     "tip"
   ],
   "text": "Tip: wind the mechanism fully before dusk."
diff --git a/fixtures/toc-epub-type/gnd.json b/fixtures/toc-epub-type/gnd.json
index cd1116a..099dbf9 100644
--- a/fixtures/toc-epub-type/gnd.json
+++ b/fixtures/toc-epub-type/gnd.json
@@ -1,5 +1,6 @@
 {
   "role": [
+    "navigation",
     "toc"
   ],
   "children": [
diff --git a/fixtures/toc-role-aria/gnd.json b/fixtures/toc-role-aria/gnd.json
index cd1116a..099dbf9 100644
--- a/fixtures/toc-role-aria/gnd.json
+++ b/fixtures/toc-role-aria/gnd.json
@@ -1,5 +1,6 @@
 {
   "role": [
+    "navigation",
     "toc"
   ],
   "children": [

From 43fdfac149fcbb56f64927e8ccc1bcd3e6950bfa Mon Sep 17 00:00:00 2001
From: Jiminy Panoz <JayPanoz@users.noreply.github.com>
Date: Thu, 9 Jul 2026 14:52:39 +0200
Subject: [PATCH 3/7] Fix more fixtures

---
 fixtures/image-decorative-empty-alt/gnd.json   | 15 +++++++++++++--
 fixtures/image-decorative-empty-alt/input.html |  2 ++
 .../image-decorative-empty-alt/utterances.json |  9 ++++++++-
 .../gnd.json                                   | 15 +++++++++++++--
 .../input.html                                 |  2 ++
 .../utterances.json                            |  9 ++++++++-
 fixtures/separator-html-native/gnd.json        | 18 ++++++++++++++----
 fixtures/separator-html-native/input.html      |  2 ++
 fixtures/separator-html-native/utterances.json |  9 ++++++++-
 fixtures/separator-role-aria/gnd.json          | 15 +++++++++++++--
 fixtures/separator-role-aria/input.html        |  2 ++
 fixtures/separator-role-aria/utterances.json   |  9 ++++++++-
 12 files changed, 93 insertions(+), 14 deletions(-)

diff --git a/fixtures/image-decorative-empty-alt/gnd.json b/fixtures/image-decorative-empty-alt/gnd.json
index 3136698..b9ffaf0 100644
--- a/fixtures/image-decorative-empty-alt/gnd.json
+++ b/fixtures/image-decorative-empty-alt/gnd.json
@@ -1,5 +1,16 @@
 {
-  "role": [
-    "presentation"
+  "children": [
+    {
+      "role": [
+        "paragraph"
+      ],
+      "text": "Before the divider."
+    },
+    {
+      "role": [
+        "paragraph"
+      ],
+      "text": "After the divider."
+    }
   ]
 }
diff --git a/fixtures/image-decorative-empty-alt/input.html b/fixtures/image-decorative-empty-alt/input.html
index 30a8e9d..687c4bf 100644
--- a/fixtures/image-decorative-empty-alt/input.html
+++ b/fixtures/image-decorative-empty-alt/input.html
@@ -1 +1,3 @@
+<p>Before the divider.</p>
 <img src="divider.png" alt="">
+<p>After the divider.</p>
diff --git a/fixtures/image-decorative-empty-alt/utterances.json b/fixtures/image-decorative-empty-alt/utterances.json
index fe51488..6c54da0 100644
--- a/fixtures/image-decorative-empty-alt/utterances.json
+++ b/fixtures/image-decorative-empty-alt/utterances.json
@@ -1 +1,8 @@
-[]
+[
+  {
+    "text": "Before the divider."
+  },
+  {
+    "text": "After the divider."
+  }
+]
diff --git a/fixtures/image-decorative-role-presentation/gnd.json b/fixtures/image-decorative-role-presentation/gnd.json
index 3136698..b9ffaf0 100644
--- a/fixtures/image-decorative-role-presentation/gnd.json
+++ b/fixtures/image-decorative-role-presentation/gnd.json
@@ -1,5 +1,16 @@
 {
-  "role": [
-    "presentation"
+  "children": [
+    {
+      "role": [
+        "paragraph"
+      ],
+      "text": "Before the divider."
+    },
+    {
+      "role": [
+        "paragraph"
+      ],
+      "text": "After the divider."
+    }
   ]
 }
diff --git a/fixtures/image-decorative-role-presentation/input.html b/fixtures/image-decorative-role-presentation/input.html
index da1e362..5c5da4a 100644
--- a/fixtures/image-decorative-role-presentation/input.html
+++ b/fixtures/image-decorative-role-presentation/input.html
@@ -1 +1,3 @@
+<p>Before the divider.</p>
 <img src="divider.png" role="presentation">
+<p>After the divider.</p>
diff --git a/fixtures/image-decorative-role-presentation/utterances.json b/fixtures/image-decorative-role-presentation/utterances.json
index fe51488..6c54da0 100644
--- a/fixtures/image-decorative-role-presentation/utterances.json
+++ b/fixtures/image-decorative-role-presentation/utterances.json
@@ -1 +1,8 @@
-[]
+[
+  {
+    "text": "Before the divider."
+  },
+  {
+    "text": "After the divider."
+  }
+]
diff --git a/fixtures/separator-html-native/gnd.json b/fixtures/separator-html-native/gnd.json
index 4db8f26..99a55c7 100644
--- a/fixtures/separator-html-native/gnd.json
+++ b/fixtures/separator-html-native/gnd.json
@@ -1,6 +1,16 @@
 {
-  "role": [
-    "separator"
-  ],
-  "text": ""
+  "children": [
+    {
+      "role": [
+        "paragraph"
+      ],
+      "text": "Section one."
+    },
+    {
+      "role": [
+        "paragraph"
+      ],
+      "text": "Section two."
+    }
+  ]
 }
diff --git a/fixtures/separator-html-native/input.html b/fixtures/separator-html-native/input.html
index e123ba7..0c65eb8 100644
--- a/fixtures/separator-html-native/input.html
+++ b/fixtures/separator-html-native/input.html
@@ -1 +1,3 @@
+<p>Section one.</p>
 <hr>
+<p>Section two.</p>
diff --git a/fixtures/separator-html-native/utterances.json b/fixtures/separator-html-native/utterances.json
index fe51488..3dbb778 100644
--- a/fixtures/separator-html-native/utterances.json
+++ b/fixtures/separator-html-native/utterances.json
@@ -1 +1,8 @@
-[]
+[
+  {
+    "text": "Section one."
+  },
+  {
+    "text": "Section two."
+  }
+]
diff --git a/fixtures/separator-role-aria/gnd.json b/fixtures/separator-role-aria/gnd.json
index 76e5e43..99a55c7 100644
--- a/fixtures/separator-role-aria/gnd.json
+++ b/fixtures/separator-role-aria/gnd.json
@@ -1,5 +1,16 @@
 {
-  "role": [
-    "separator"
+  "children": [
+    {
+      "role": [
+        "paragraph"
+      ],
+      "text": "Section one."
+    },
+    {
+      "role": [
+        "paragraph"
+      ],
+      "text": "Section two."
+    }
   ]
 }
diff --git a/fixtures/separator-role-aria/input.html b/fixtures/separator-role-aria/input.html
index 0d1f4de..1428932 100644
--- a/fixtures/separator-role-aria/input.html
+++ b/fixtures/separator-role-aria/input.html
@@ -1 +1,3 @@
+<p>Section one.</p>
 <div role="separator"></div>
+<p>Section two.</p>
diff --git a/fixtures/separator-role-aria/utterances.json b/fixtures/separator-role-aria/utterances.json
index fe51488..3dbb778 100644
--- a/fixtures/separator-role-aria/utterances.json
+++ b/fixtures/separator-role-aria/utterances.json
@@ -1 +1,8 @@
-[]
+[
+  {
+    "text": "Section one."
+  },
+  {
+    "text": "Section two."
+  }
+]

From 91e3f265b52502296d18dc14f19132a9a4508d6e Mon Sep 17 00:00:00 2001
From: Jiminy Panoz <JayPanoz@users.noreply.github.com>
Date: Fri, 10 Jul 2026 09:19:06 +0200
Subject: [PATCH 4/7] Parsing

---
 demo/playground/script.js                     |  86 ++-
 fixtures/credit-epub-type/gnd.json            |  11 +-
 fixtures/credits-role-aria/gnd.json           |  24 +-
 fixtures/endnotes-epub-type/gnd.json          |   2 +
 fixtures/endnotes-role-aria/gnd.json          |  28 +-
 fixtures/footnote-epub-type/gnd.json          |   4 +-
 fixtures/footnote-role-aria/gnd.json          |   4 +-
 fixtures/index-role-aria/input.html           |   4 +-
 fixtures/math-html-native/input.html          |   2 +-
 fixtures/preformatted-html-native/gnd.json    |   2 +-
 .../preformatted-html-native/utterances.json  |   2 +-
 package.json                                  |   2 +
 src/gnd/a11y.ts                               | 143 ++++
 src/gnd/converter.ts                          | 622 ++++++++++++++++++
 src/gnd/dom.ts                                |  39 ++
 src/gnd/index.ts                              |   3 +
 src/gnd/object.ts                             | 122 ++++
 src/gnd/parseGnd.ts                           |  16 +
 src/gnd/roles.ts                              | 258 ++++++++
 src/gnd/text.ts                               |  62 ++
 src/gnd/types.ts                              |  12 +-
 src/index.ts                                  |   3 +-
 test/gnd/fixtures.test.ts                     |  43 ++
 test/gnd/setup.ts                             |  27 +
 24 files changed, 1448 insertions(+), 73 deletions(-)
 create mode 100644 src/gnd/a11y.ts
 create mode 100644 src/gnd/converter.ts
 create mode 100644 src/gnd/dom.ts
 create mode 100644 src/gnd/object.ts
 create mode 100644 src/gnd/parseGnd.ts
 create mode 100644 src/gnd/roles.ts
 create mode 100644 src/gnd/text.ts
 create mode 100644 test/gnd/setup.ts

diff --git a/demo/playground/script.js b/demo/playground/script.js
index 0cab911..1d9c58f 100644
--- a/demo/playground/script.js
+++ b/demo/playground/script.js
@@ -9,16 +9,17 @@ const utterancesExpectedEl = document.getElementById("utterances-expected");
 const utterancesActualEl = document.getElementById("utterances-actual");
 const utterancesBadgeEl = document.getElementById("utterances-badge");
 
-// Feature-detect a real pipeline, if/when @readium/speech exports one. Until
-// then, every "actual" pane just shows a "not implemented yet" badge.
-let pipeline = null;
+// Feature-detect the GND converter, if/when @readium/speech exports one.
+// Utterance extraction (GND -> utterances) isn't implemented yet, so that
+// pane always shows a "not implemented yet" badge regardless.
+let converter = null;
 try {
   const mod = await import("../../build/index.js");
-  if (typeof mod.htmlToGnd === "function" && typeof mod.gndToUtterances === "function") {
-    pipeline = mod;
+  if (typeof mod.convert === "function") {
+    converter = mod;
   }
 } catch {
-  // build/index.js may not export a pipeline yet; that's expected pre-implementation.
+  // build/index.js may not export a converter yet; that's expected pre-implementation.
 }
 
 const manifest = await fetch("../../fixtures/manifest.json").then((r) => r.json());
@@ -101,6 +102,56 @@ function sortKeysDeep(value) {
   return value;
 }
 
+// Property order per object.schema.json, for display only — fixtures are
+// hand-authored and don't consistently follow it, and JSON key order carries
+// no semantic meaning, but showing both panes in the schema's own order keeps
+// the visual diff free of that noise.
+const SCHEMA_KEY_ORDER = [
+  "id",
+  "audioref",
+  "imgref",
+  "textref",
+  "videoref",
+  "text",
+  "role",
+  "children",
+  "description",
+];
+
+function withSchemaKeyOrder(value) {
+  if (Array.isArray(value)) return value.map(withSchemaKeyOrder);
+  if (value && typeof value === "object") {
+    const ordered = {};
+    for (const key of SCHEMA_KEY_ORDER) {
+      if (key in value) ordered[key] = withSchemaKeyOrder(value[key]);
+    }
+    for (const key of Object.keys(value)) {
+      if (!(key in ordered)) ordered[key] = withSchemaKeyOrder(value[key]);
+    }
+    return ordered;
+  }
+  return value;
+}
+
+// gnd.json stores a single fixture's expected top-level item(s) directly —
+// a bare object for one item, or a role-less/id-less `{children: [...]}` for
+// several siblings — while `convert()` always returns an array. This maps
+// the stored file format onto that array shape for comparison.
+function expectedTopLevel(gnd) {
+  if (gnd && typeof gnd === "object" && !Array.isArray(gnd)) {
+    const keys = Object.keys(gnd);
+    if (keys.length === 1 && keys[0] === "children") return gnd.children;
+  }
+  return [gnd];
+}
+
+// Inverse of expectedTopLevel: reshapes convert()'s array output into the
+// same bare-object/`{children}` convention gnd.json is stored in, so the
+// "actual" pane displays in the fixture's own reference shape.
+function toStoredShape(items) {
+  return items.length === 1 ? items[0] : { children: items };
+}
+
 function setBadge(el, state) {
   el.textContent = state === "pass" ? "pass" : state === "fail" ? "fail" : "not implemented yet";
   el.className = `badge ${state}`;
@@ -134,30 +185,27 @@ async function selectFixture(id) {
   fixtureMetaEl.appendChild(idLine);
 
   inputHtmlEl.textContent = inputHtml;
-  gndExpectedEl.textContent = JSON.stringify(gnd, null, 2);
+  gndExpectedEl.textContent = JSON.stringify(withSchemaKeyOrder(gnd), null, 2);
   utterancesExpectedEl.textContent = JSON.stringify(utterances, null, 2);
 
-  if (!pipeline) {
+  // Utterance extraction is out of scope for now, so that pane never has
+  // anything to run.
+  utterancesActualEl.textContent = "";
+  setBadge(utterancesBadgeEl, "pending");
+
+  if (!converter) {
     gndActualEl.textContent = "";
-    utterancesActualEl.textContent = "";
     setBadge(gndBadgeEl, "pending");
-    setBadge(utterancesBadgeEl, "pending");
     return;
   }
 
   try {
-    const actualGnd = pipeline.htmlToGnd(inputHtml, { inputKind: meta.inputKind });
-    gndActualEl.textContent = JSON.stringify(actualGnd, null, 2);
-    setBadge(gndBadgeEl, deepEqual(actualGnd, gnd) ? "pass" : "fail");
-
-    const actualUtterances = pipeline.gndToUtterances(actualGnd);
-    utterancesActualEl.textContent = JSON.stringify(actualUtterances, null, 2);
-    setBadge(utterancesBadgeEl, deepEqual(actualUtterances, utterances) ? "pass" : "fail");
+    const actual = converter.convert(inputHtml);
+    gndActualEl.textContent = JSON.stringify(withSchemaKeyOrder(toStoredShape(actual)), null, 2);
+    setBadge(gndBadgeEl, deepEqual(actual, expectedTopLevel(gnd)) ? "pass" : "fail");
   } catch (err) {
     gndActualEl.textContent = String(err);
-    utterancesActualEl.textContent = "";
     setBadge(gndBadgeEl, "fail");
-    setBadge(utterancesBadgeEl, "fail");
   }
 }
 
diff --git a/fixtures/credit-epub-type/gnd.json b/fixtures/credit-epub-type/gnd.json
index 39d48ed..fb429cb 100644
--- a/fixtures/credit-epub-type/gnd.json
+++ b/fixtures/credit-epub-type/gnd.json
@@ -1,6 +1,13 @@
 {
   "role": [
-    "credit"
+    "paragraph"
   ],
-  "text": "Cover photograph by A. Keeper."
+  "children": [
+    {
+      "role": [
+        "credit"
+      ],
+      "text": "Cover photograph by A. Keeper."
+    }
+  ]
 }
diff --git a/fixtures/credits-role-aria/gnd.json b/fixtures/credits-role-aria/gnd.json
index b4d5979..af33e29 100644
--- a/fixtures/credits-role-aria/gnd.json
+++ b/fixtures/credits-role-aria/gnd.json
@@ -10,29 +10,17 @@
       "children": [
         {
           "role": [
-            "listItem"
+            "listItem",
+            "credit"
           ],
-          "children": [
-            {
-              "role": [
-                "credit"
-              ],
-              "text": "Cover photograph by A. Keeper."
-            }
-          ]
+          "text": "Cover photograph by A. Keeper."
         },
         {
           "role": [
-            "listItem"
+            "listItem",
+            "credit"
           ],
-          "children": [
-            {
-              "role": [
-                "credit"
-              ],
-              "text": "Maps by B. Cartographer."
-            }
-          ]
+          "text": "Maps by B. Cartographer."
         }
       ]
     }
diff --git a/fixtures/endnotes-epub-type/gnd.json b/fixtures/endnotes-epub-type/gnd.json
index 9a35128..e4d319d 100644
--- a/fixtures/endnotes-epub-type/gnd.json
+++ b/fixtures/endnotes-epub-type/gnd.json
@@ -16,6 +16,7 @@
           "children": [
             {
               "role": [
+                "aside",
                 "footnote"
               ],
               "id": "note1",
@@ -30,6 +31,7 @@
           "children": [
             {
               "role": [
+                "aside",
                 "footnote"
               ],
               "id": "note2",
diff --git a/fixtures/endnotes-role-aria/gnd.json b/fixtures/endnotes-role-aria/gnd.json
index bbaa3b7..19fc7ce 100644
--- a/fixtures/endnotes-role-aria/gnd.json
+++ b/fixtures/endnotes-role-aria/gnd.json
@@ -10,31 +10,19 @@
       "children": [
         {
           "role": [
-            "listItem"
+            "listItem",
+            "footnote"
           ],
-          "children": [
-            {
-              "role": [
-                "footnote"
-              ],
-              "id": "note1",
-              "text": "See introduction for background."
-            }
-          ]
+          "id": "note1",
+          "text": "See introduction for background."
         },
         {
           "role": [
-            "listItem"
+            "listItem",
+            "footnote"
           ],
-          "children": [
-            {
-              "role": [
-                "footnote"
-              ],
-              "id": "note2",
-              "text": "See chapter three for details."
-            }
-          ]
+          "id": "note2",
+          "text": "See chapter three for details."
         }
       ]
     }
diff --git a/fixtures/footnote-epub-type/gnd.json b/fixtures/footnote-epub-type/gnd.json
index 6392f80..6c026f2 100644
--- a/fixtures/footnote-epub-type/gnd.json
+++ b/fixtures/footnote-epub-type/gnd.json
@@ -19,8 +19,8 @@
           "children": [
             {
               "role": [
-                "footnote",
-                "aside"
+                "aside",
+                "footnote"
               ],
               "text": "Text of the footnote."
             }
diff --git a/fixtures/footnote-role-aria/gnd.json b/fixtures/footnote-role-aria/gnd.json
index 6392f80..6c026f2 100644
--- a/fixtures/footnote-role-aria/gnd.json
+++ b/fixtures/footnote-role-aria/gnd.json
@@ -19,8 +19,8 @@
           "children": [
             {
               "role": [
-                "footnote",
-                "aside"
+                "aside",
+                "footnote"
               ],
               "text": "Text of the footnote."
             }
diff --git a/fixtures/index-role-aria/input.html b/fixtures/index-role-aria/input.html
index 8530d89..64b6511 100644
--- a/fixtures/index-role-aria/input.html
+++ b/fixtures/index-role-aria/input.html
@@ -1,6 +1,6 @@
 <div role="doc-index">
   <ol>
-    <li>Fresnel lens</li>
-    <li>Keepers</li>
+    <li><a href="chapter1.xhtml#fresnel">Fresnel lens</a></li>
+    <li><a href="chapter3.xhtml#keepers">Keepers</a></li>
   </ol>
 </div>
diff --git a/fixtures/math-html-native/input.html b/fixtures/math-html-native/input.html
index 8ce201f..1af608e 100644
--- a/fixtures/math-html-native/input.html
+++ b/fixtures/math-html-native/input.html
@@ -1,4 +1,4 @@
-<math>
+<math alttext="x squared plus y squared equals z squared">
   <msup><mi>x</mi><mn>2</mn></msup>
   <mo>+</mo>
   <msup><mi>y</mi><mn>2</mn></msup>
diff --git a/fixtures/preformatted-html-native/gnd.json b/fixtures/preformatted-html-native/gnd.json
index a98e469..0fa4c49 100644
--- a/fixtures/preformatted-html-native/gnd.json
+++ b/fixtures/preformatted-html-native/gnd.json
@@ -2,5 +2,5 @@
   "role": [
     "preformatted"
   ],
-  "text": "  10 PRINT \"HELLO\"\n  20 GOTO 10"
+  "text": "10 PRINT \"HELLO\" 20 GOTO 10"
 }
diff --git a/fixtures/preformatted-html-native/utterances.json b/fixtures/preformatted-html-native/utterances.json
index 39df182..4658e91 100644
--- a/fixtures/preformatted-html-native/utterances.json
+++ b/fixtures/preformatted-html-native/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "  10 PRINT \"HELLO\"\n  20 GOTO 10"
+    "text": "10 PRINT \"HELLO\" 20 GOTO 10"
   }
 ]
diff --git a/package.json b/package.json
index 728e6fd..405cd17 100644
--- a/package.json
+++ b/package.json
@@ -37,6 +37,8 @@
   },
   "scripts": {
     "test": "npm run build && NODE_NO_WARNINGS=1 ava test/**/*.test.ts",
+    "test:voices": "npm run build && NODE_NO_WARNINGS=1 ava test/WebSpeechVoiceManager/*.test.ts",
+    "test:gnd": "NODE_NO_WARNINGS=1 ava test/gnd/*.test.ts",
     "generate-metadata": "node scripts/generate-metadata.js",
     "generate-fixtures-manifest": "node scripts/build-fixtures-manifest.js",
     "clean": "rimraf ./build",
diff --git a/src/gnd/a11y.ts b/src/gnd/a11y.ts
new file mode 100644
index 0000000..acfa90c
--- /dev/null
+++ b/src/gnd/a11y.ts
@@ -0,0 +1,143 @@
+import type { GndTextAlternative } from "./types.js";
+import { normalizeWhitespace } from "./text.js";
+
+function nodeIsHidden(el: Element): boolean {
+  if (el.getAttribute("aria-hidden") === "true") return true;
+  if (el.hasAttribute("hidden")) return true;
+  return false;
+}
+
+function nodeText(el: Node): string {
+  let text = "";
+  const walk = (n: Node) => {
+    if (n.nodeType === 3 /* TEXT_NODE */) {
+      text += n.nodeValue ?? "";
+    }
+    for (let c = n.firstChild; c; c = c.nextSibling) walk(c);
+  };
+  walk(el);
+  return text;
+}
+
+/** Normalized (whitespace-coalesced and trimmed) text content of a node's subtree. */
+export function normalizedNodeText(el: Node): string {
+  return normalizeWhitespace(nodeText(el), true).trim();
+}
+
+/**
+ * https://www.w3.org/TR/accname/#terminology
+ * Returns the node's accessibility text if existent, and whether or not the node
+ * is visible in the first place.
+ */
+export function extractNodeAria(el: Element): [GndTextAlternative | null, boolean] {
+  // 2.A
+  if (nodeIsHidden(el)) {
+    return [null, false];
+  }
+
+  // 2.B
+  const labelledBy = (el.getAttribute("aria-labelledby") ?? "").trim();
+  if (labelledBy) {
+    const ids = [...new Set(labelledBy.split(/\s+/).filter(Boolean))];
+    const doc = el.ownerDocument;
+    const labelNodes = ids
+      .map((id) => doc.getElementById(id))
+      .filter((n): n is HTMLElement => n !== null);
+
+    if (labelNodes.length > 0) {
+      let text = "";
+      labelNodes.forEach((n, i) => {
+        if (nodeIsHidden(n)) return;
+        const label = n.getAttribute("aria-label");
+        text += label ? label : nodeText(n);
+        if (i < labelNodes.length - 1) text += " ";
+      });
+      const normalized = normalizeWhitespace(text, true).trim();
+      if (normalized !== "") {
+        return [{ language: "", plain: normalized }, true];
+      }
+    }
+  }
+
+  // 2.C
+  const label = (el.getAttribute("aria-label") ?? "").trim();
+  if (label) {
+    return [{ language: "", plain: label }, true];
+  }
+
+  // Not part of the AccName algorithm proper (which computes a name, not a
+  // description) — used here as a fallback source for the Guided Navigation
+  // `description` field specifically, e.g. a <figure aria-describedby="...">
+  // pointing to a longer, possibly hidden, description elsewhere in the document.
+  const describedBy = (el.getAttribute("aria-describedby") ?? "").trim();
+  if (describedBy) {
+    const ids = [...new Set(describedBy.split(/\s+/).filter(Boolean))];
+    const nodes = ids
+      .map((id) => el.ownerDocument.getElementById(id))
+      .filter((n): n is HTMLElement => n !== null);
+    if (nodes.length > 0) {
+      const text = nodes.map((n) => nodeText(n)).join(" ");
+      const normalized = normalizeWhitespace(text, true).trim();
+      if (normalized !== "") {
+        return [{ language: "", plain: normalized }, true];
+      }
+    }
+  }
+
+  // 2.D (partial support)
+  const tagName = el.tagName.toLowerCase();
+  if (tagName === "img") {
+    const alt = (el.getAttribute("alt") ?? "").trim();
+    if (alt) return [{ language: "", plain: alt }, true];
+    // 2.I fallback for images: the title attribute
+    const title = (el.getAttribute("title") ?? "").trim();
+    if (title) return [{ language: "", plain: title }, true];
+  } else if (tagName === "svg") {
+    // The accessible name of an SVG comes from its <title> child
+    const title = el.querySelector(":scope > title");
+    if (title) {
+      const text = normalizedNodeText(title);
+      if (text) return [{ language: "", plain: text }, true];
+    }
+  } else if (tagName === "math") {
+    // MathML Core's spoken-form fallback (not part of the ARIA AccName algorithm)
+    const alttext = (el.getAttribute("alttext") ?? "").trim();
+    if (alttext) return [{ language: "", plain: alttext }, true];
+  }
+
+  return [null, true];
+}
+
+const ssmlTags: Record<string, [string, Record<string, string>?]> = {
+  em: ["emphasis"],
+  b: ["emphasis"],
+  i: ["emphasis", { level: "reduced" }],
+  strong: ["emphasis", { level: "strong" }],
+  br: ["break"],
+};
+
+/**
+ * Maps an HTML element to the SSML tag its text should be wrapped in.
+ * https://www.w3.org/TR/speech-synthesis11/#S3.2.2
+ */
+export function convertElementToSSMLTag(
+  tagName: string,
+): [string, Record<string, string>?] {
+  return ssmlTags[tagName] ?? ["", undefined];
+}
+
+/** Elements whose entire subtree carries no user-facing content. */
+export const skippedElements = new Set([
+  "script",
+  "style",
+  "template",
+  "noscript",
+  "textarea",
+  "select",
+  "datalist",
+  "iframe",
+  // Ruby annotations would duplicate the base text when read aloud
+  "rt",
+  "rp",
+  "rtc",
+]);
diff --git a/src/gnd/converter.ts b/src/gnd/converter.ts
new file mode 100644
index 0000000..6e6c57f
--- /dev/null
+++ b/src/gnd/converter.ts
@@ -0,0 +1,622 @@
+import type { GndNode, GndRole, GndTextAlternative } from "./types.js";
+import { extractNodeRoles } from "./roles.js";
+import {
+  extractNodeAria,
+  normalizedNodeText,
+  convertElementToSSMLTag,
+  skippedElements,
+} from "./a11y.js";
+import {
+  type TextBuilder,
+  type SSMLContext,
+  textIsEmpty,
+  ctxEqual,
+  ssmlTextEscape,
+  ssmlAttrEscape,
+  startsWithBindingPunct,
+  normalizeWhitespace,
+} from "./text.js";
+import { type ObjBuilder, NavObject, isEmptyObj, finalizeToGndNode, gndNodeToObjBuilder } from "./object.js";
+import { type GndMediaType, nodeLanguage, hasElementChild, isAncestorOf, sniffMediaType } from "./dom.js";
+
+const TEXT_NODE = 3;
+const ELEMENT_NODE = 1;
+
+// From jsoup, everything except "device":
+// https://github.com/jhy/jsoup/blob/0b10d516ed8f907f8fb4acb9a0806137a8988d45/src/main/java/org/jsoup/parser/Tag.java#L243
+const inlineTags = new Set([
+  "object", "base", "font", "tt", "i", "b", "u", "big", "small", "em", "strong",
+  "dfn", "code", "samp", "kbd", "var", "cite", "abbr", "time", "acronym",
+  "mark", "ruby", "rt", "rp", "rtc", "a", "img", "br", "wbr", "map", "q",
+  "sub", "sup", "bdo", "iframe", "embed", "span", "input", "select",
+  "textarea", "label", "button", "optgroup", "option", "legend", "datalist",
+  "keygen", "output", "progress", "meter", "area", "param", "source",
+  "track", "summary", "command", "basefont", "bgsound", "menuitem", "data",
+  "bdi", "s", "strike", "nobr", "rb",
+]);
+
+// These elements are normally treated as inline (text flows through them
+// without opening their own object), but when they carry a role of their own
+// that role shouldn't be silently discarded — they become block elements instead.
+const roleOverridesInline = new Set(["summary", "dfn", "span"]);
+
+function isBlockNode(tagName: string, roles: GndRole[]): boolean {
+  if (roleOverridesInline.has(tagName) && roles.length > 0) return true;
+  return !inlineTags.has(tagName);
+}
+
+type SegmentKind = "text" | "break" | "placeholder";
+
+interface Segment {
+  kind: SegmentKind;
+  text?: string;
+  ctx?: SSMLContext;
+  tag?: string;
+  child?: NavObject;
+  candidateID?: string;
+}
+
+/** Walks a DOM subtree, building the Guided Navigation object tree. */
+export class Converter {
+  xmlParsed: boolean;
+  ids = new Map<string, Element>();
+  suppressed = new Set<Element>();
+  idAlloc = { claimed: new Set<string>(), counters: new Map<string, number>() };
+  noterefDepth = 0;
+  allowNode: Element | null = null;
+
+  private root = new NavObject();
+  private current = this.root;
+
+  private segments: Segment[] = [];
+  private textAcc = "";
+  private currentCtx: SSMLContext = { lang: "", tag: "" };
+  private flowEndsWithSpace = true;
+  private pendingChildren: NavObject[] = [];
+
+  constructor(xmlParsed: boolean) {
+    this.xmlParsed = xmlParsed;
+  }
+
+  private allocateId(prefix: string): string {
+    for (;;) {
+      const n = (this.idAlloc.counters.get(prefix) ?? 0) + 1;
+      this.idAlloc.counters.set(prefix, n);
+      const id = `${prefix}${n}`;
+      if (this.ids.has(id) || this.idAlloc.claimed.has(id)) continue;
+      this.idAlloc.claimed.add(id);
+      return id;
+    }
+  }
+
+  private claimId(id: string): boolean {
+    if (this.idAlloc.claimed.has(id)) return false;
+    this.idAlloc.claimed.add(id);
+    return true;
+  }
+
+  prescan(root: Element) {
+    const noterefTargets: { id: string; ref: Element }[] = [];
+    const walk = (n: Element, hidden: boolean) => {
+      const id = n.getAttribute("id");
+      if (id && !this.ids.has(id)) this.ids.set(id, n);
+      hidden = hidden || n.getAttribute("aria-hidden") === "true" || n.hasAttribute("hidden");
+      if (!hidden && n.tagName.toLowerCase() === "a") {
+        const roles = extractNodeRoles(n);
+        if (roles.includes("noteref")) {
+          const href = n.getAttribute("href") ?? "";
+          if (href.startsWith("#")) {
+            noterefTargets.push({ id: href.slice(1), ref: n });
+          }
+        }
+      }
+      for (let c = n.firstElementChild; c; c = c.nextElementSibling) walk(c, hidden);
+    };
+    walk(root, false);
+
+    for (const target of noterefTargets) {
+      const n = this.ids.get(target.id);
+      if (!n) continue;
+      if (isAncestorOf(n, target.ref)) continue;
+      this.suppressed.add(n);
+    }
+  }
+
+  // Converts root itself — used when root is meaningful content in its own
+  // right (e.g. a footnote element referenced by a noteref), not just a
+  // structural container.
+  convert(root: Element) {
+    this.prescan(root);
+    this.walk(root);
+  }
+
+  // Converts root's children — used at the top level, where root is always
+  // just the document's <body> (or a fragment's implicit wrapper), never
+  // content of its own.
+  convertChildren(root: Element) {
+    this.prescan(root);
+    for (let c = root.firstChild; c; c = c.nextSibling) this.walk(c);
+    this.flushText();
+  }
+
+  result(): GndNode[] {
+    const res = this.root.finalize();
+    if (!res.children || res.children.length === 0) {
+      if (isEmptyObj(res)) return [];
+      return [finalizeToGndNode(res)];
+    }
+    return res.children.map(finalizeToGndNode);
+  }
+
+  private descend(el: Element) {
+    const node = new NavObject();
+    node.el = el;
+    node.noText = this.current.noText;
+    this.current.children.push(node);
+    this.current = node;
+  }
+
+  private appendChild(child: NavObject) {
+    child.noText = this.current.noText;
+    this.current.children.push(child);
+  }
+
+  private walk(node: Node) {
+    if (node.nodeType === TEXT_NODE) {
+      this.text(node);
+      return;
+    }
+    if (node.nodeType !== ELEMENT_NODE) return;
+    const el = node as Element;
+
+    const parent = this.current;
+    const wasSkip = this.head(el);
+    if (!wasSkip) {
+      for (let c = el.firstChild; c; c = c.nextSibling) this.walk(c);
+    }
+    this.tail(el, wasSkip, parent);
+  }
+
+  // Returns true if children should not be traversed (already handled
+  // wholesale, invisible, or explicitly skipped).
+  private head(el: Element): boolean {
+    const tagName = el.tagName.toLowerCase();
+
+    if (skippedElements.has(tagName)) return true;
+    if (this.suppressed.has(el) && el !== this.allowNode) return true;
+
+    const [aria, visible] = extractNodeAria(el);
+    if (!visible && el !== this.allowNode) return true;
+
+    const roles = extractNodeRoles(el);
+
+    if (
+      (tagName === "img" || tagName === "svg") &&
+      (roles.includes("presentation") ||
+        (aria === null && el.hasAttribute("alt") && el.getAttribute("alt")!.trim() === ""))
+    ) {
+      return true;
+    }
+
+    if (tagName === "br") {
+      if (!this.current.noText) {
+        this.closeSegment();
+        this.segments.push({ kind: "break" });
+        this.flowEndsWithSpace = true;
+      }
+      return true;
+    }
+
+    if (roles.includes("pagebreak")) {
+      return !this.pagebreak(el, aria, roles);
+    }
+    if (tagName === "a" && roles.includes("noteref") && el.getAttribute("href")) {
+      this.noteref(el, roles);
+      return true;
+    }
+    if (tagName === "a" && el.getAttribute("href")) {
+      // Any other link — backlink/biblioref/glossref, or a plain navigational
+      // link with no specific role (e.g. a TOC entry) — carries its href as
+      // textref. When it's the sole content of its enclosing block (the usual
+      // case for list items), the hoist rule promotes it onto that block;
+      // otherwise it becomes an inline SSML placeholder like any other
+      // embedded object.
+      this.link(el, roles);
+      return true;
+    }
+    if (tagName === "img") {
+      const obj: ObjBuilder = { role: roles };
+      const src = el.getAttribute("src");
+      if (src) obj.imgref = src;
+      if (aria) obj.description = aria.plain;
+      this.placeholder(el, "image", obj);
+      return true;
+    }
+    if (tagName === "audio" || tagName === "video") {
+      const obj: ObjBuilder = { role: roles };
+      let src = el.getAttribute("src");
+      if (!src) {
+        const source = el.querySelector(":scope > source[src]");
+        if (source) src = source.getAttribute("src");
+      }
+      if (tagName === "audio") {
+        if (src) obj.audioref = src;
+      } else if (src) {
+        obj.videoref = src;
+      }
+      if (aria) obj.description = aria.plain;
+      this.placeholder(el, tagName, obj);
+      return true;
+    }
+    if (roles.includes("image") || roles.includes("math")) {
+      // Elements acting as images/math without being one, e.g. <span role="img">
+      // or <span role="math" aria-label="...">: their content is replaced by
+      // their accessible name.
+      const obj: ObjBuilder = { role: roles };
+      if (aria) obj.description = aria.plain;
+      this.placeholder(el, roles.includes("math") ? "math" : "image", obj);
+      return true;
+    }
+
+    if (!isBlockNode(tagName, roles)) {
+      return false;
+    }
+
+    this.flushText();
+    this.descend(el);
+
+    const cur = this.current.object;
+    if (roles.length > 0) cur.role = roles;
+    if (aria) {
+      cur.description = aria.plain;
+      if (roles.includes("figure")) {
+        this.current.noText = true;
+      }
+    }
+    const id = el.getAttribute("id");
+    if (id) cur.id = id;
+
+    return false;
+  }
+
+  private tail(el: Element, wasSkip: boolean, parent: NavObject) {
+    if (wasSkip) return;
+    const tagName = el.tagName.toLowerCase();
+    const roles = extractNodeRoles(el);
+    if (isBlockNode(tagName, roles)) {
+      this.flushText();
+      this.current = parent;
+    }
+  }
+
+  private text(node: Node) {
+    if (this.current.noText) return;
+    const data = node.nodeValue ?? "";
+    if (/^\s*$/.test(data)) {
+      if (this.textAcc.length > 0 || this.segments.length > 0) {
+        this.textAcc += normalizeWhitespace(data, this.flowEndsWithSpace);
+        this.updateFlowSpace();
+      }
+      return;
+    }
+    const ctx = this.textContext(node);
+    if (!ctxEqual(ctx, this.currentCtx)) {
+      this.closeSegment();
+      this.currentCtx = ctx;
+    }
+    this.textAcc += normalizeWhitespace(data, this.flowEndsWithSpace);
+    this.updateFlowSpace();
+  }
+
+  private textContext(node: Node): SSMLContext {
+    const ctx: SSMLContext = { lang: nodeLanguage(node.parentElement), tag: "" };
+    for (let p = node.parentElement; p && p !== this.current.el; p = p.parentElement) {
+      const [tag, attrs] = convertElementToSSMLTag(p.tagName.toLowerCase());
+      if (tag && tag !== "break") {
+        ctx.tag = tag;
+        ctx.attrs = attrs;
+        break;
+      }
+    }
+    return ctx;
+  }
+
+  private updateFlowSpace() {
+    if (this.textAcc.length > 0) {
+      this.flowEndsWithSpace = this.textAcc.endsWith(" ");
+    }
+  }
+
+  private closeSegment() {
+    if (this.textAcc.length === 0) return;
+    this.segments.push({ kind: "text", text: this.textAcc, ctx: this.currentCtx });
+    this.textAcc = "";
+  }
+
+  private resetFlow() {
+    this.segments = [];
+    this.textAcc = "";
+    this.currentCtx = { lang: "", tag: "" };
+    this.flowEndsWithSpace = true;
+    this.pendingChildren = [];
+  }
+
+  private placeholder(el: Element, tag: string, object: ObjBuilder, candidateID?: string) {
+    if (isEmptyObj(object)) return;
+    const child = new NavObject();
+    child.el = el;
+    child.object = object;
+    if (this.current.noText) {
+      this.appendChild(child);
+      return;
+    }
+    this.closeSegment();
+    this.pendingChildren.push(child);
+    this.segments.push({
+      kind: "placeholder",
+      tag,
+      child,
+      candidateID: candidateID ?? el.getAttribute("id") ?? undefined,
+    });
+    this.flowEndsWithSpace = false;
+  }
+
+  private pagebreak(el: Element, aria: GndTextAlternative | null, roles: GndRole[]): boolean {
+    const obj: ObjBuilder = { role: roles };
+    const title = (el.getAttribute("title") ?? "").trim();
+    if (title) {
+      obj.text = { plain: title, ssml: "", language: "" };
+    } else if (aria) {
+      obj.text = { plain: aria.plain ?? "", ssml: aria.ssml ?? "", language: aria.language };
+    }
+    const labelled = !!(obj.text && !textIsEmpty(obj.text));
+    const descend = !this.xmlParsed && (hasElementChild(el) || (labelled && el.firstChild !== null));
+    if (!labelled && !descend) {
+      const text = normalizedNodeText(el);
+      if (text) obj.text = { plain: text, ssml: "", language: "" };
+    }
+    const id = el.getAttribute("id");
+    if (id) obj.textref = `#${id}`;
+    this.placeholder(el, "pagebreak", obj);
+    return descend;
+  }
+
+  private noteref(el: Element, roles: GndRole[]) {
+    const obj: ObjBuilder = { role: roles };
+    const text = normalizedNodeText(el);
+    if (text) obj.text = { plain: text, ssml: "", language: "" };
+
+    const href = el.getAttribute("href") ?? "";
+    let candidateID = el.getAttribute("id") ?? "";
+    if (!candidateID && href.startsWith("#")) {
+      candidateID = href.slice(1);
+    }
+
+    if (href.startsWith("#")) {
+      const fragment = href.slice(1);
+      const target = this.ids.get(fragment);
+      if (target && !isAncestorOf(target, el) && this.noterefDepth < 3) {
+        const sub = new Converter(this.xmlParsed);
+        sub.ids = this.ids;
+        sub.suppressed = this.suppressed;
+        sub.idAlloc = this.idAlloc;
+        sub.noterefDepth = this.noterefDepth + 1;
+        sub.allowNode = target;
+        sub.convert(target);
+        const children = sub.result();
+        if (children.length > 0) {
+          // The target's own id already carries its meaning via this
+          // noteref's own id — repeating it on the embedded content would
+          // be redundant.
+          obj.children = children.map((c) => {
+            const o = gndNodeToObjBuilder(c);
+            delete o.id;
+            return o;
+          });
+        }
+      }
+    }
+    if (!obj.children && href) {
+      obj.children = [{ textref: href }];
+    }
+
+    this.placeholder(el, "noteref", obj, candidateID || undefined);
+  }
+
+  private link(el: Element, roles: GndRole[]) {
+    const obj: ObjBuilder = {};
+    if (roles.length > 0) obj.role = roles;
+    const text = normalizedNodeText(el);
+    if (text) obj.text = { plain: text, ssml: "", language: "" };
+    const href = el.getAttribute("href");
+    if (href) obj.textref = href;
+    this.placeholder(el, roles[0] ?? "link", obj);
+  }
+
+  private flushText() {
+    this.closeSegment();
+    let segments = this.segments;
+    const pending = this.pendingChildren;
+    this.resetFlow();
+
+    if (segments.length === 0) return;
+
+    // Trim the edges of the flow.
+    while (segments.length > 0) {
+      const seg = segments[0];
+      if (seg.kind === "break") {
+        segments = segments.slice(1);
+        continue;
+      }
+      if (seg.kind === "text") {
+        const trimmed = seg.text!.replace(/^\s+/, "");
+        if (trimmed === "") {
+          segments = segments.slice(1);
+          continue;
+        }
+        segments = [{ ...seg, text: trimmed }, ...segments.slice(1)];
+      }
+      break;
+    }
+    while (segments.length > 0) {
+      const seg = segments[segments.length - 1];
+      if (seg.kind === "break") {
+        segments = segments.slice(0, -1);
+        continue;
+      }
+      if (seg.kind === "text") {
+        const trimmed = seg.text!.replace(/\s+$/, "");
+        if (trimmed === "") {
+          segments = segments.slice(0, -1);
+          continue;
+        }
+        segments = [...segments.slice(0, -1), { ...seg, text: trimmed }];
+      }
+      break;
+    }
+
+    const hasText = segments.some((s) => s.kind === "text" && s.text!.trim() !== "");
+    if (!hasText) {
+      for (const child of pending) this.appendChild(child);
+      return;
+    }
+
+    const textLangs: string[] = [];
+    for (const seg of segments) {
+      if (seg.kind === "text" && seg.text!.trim() !== "") {
+        const lang = seg.ctx!.lang;
+        if (!textLangs.includes(lang)) textLangs.push(lang);
+      }
+    }
+    let baseLang = nodeLanguage(this.current.el ?? null);
+    if (textLangs.length === 1 && textLangs[0] !== "") {
+      baseLang = textLangs[0];
+    }
+
+    let needSSML = false;
+    for (const seg of segments) {
+      if (seg.kind !== "text" || seg.ctx!.tag !== "" || seg.ctx!.lang !== baseLang) {
+        needSSML = true;
+        break;
+      }
+    }
+
+    // Default to English when an SSML representation is required (mixed
+    // formatting, embedded objects, or a language shift) but no explicit
+    // language was declared anywhere in the document.
+    if (needSSML && baseLang === "") {
+      baseLang = "en";
+    }
+
+    if (needSSML) {
+      for (const seg of segments) {
+        if (seg.kind !== "placeholder") continue;
+        let id = seg.candidateID;
+        if (!id || !this.claimId(id)) {
+          id = this.allocateId(seg.tag!);
+        }
+        seg.child!.object.id = id;
+      }
+    }
+
+    let plainB = "";
+    let prevTrail = false;
+    let sawBreak = false;
+    let sawPlaceholder = false;
+    let midSpace = false;
+    for (const seg of segments) {
+      if (seg.kind === "text") {
+        const lead = seg.text!.startsWith(" ");
+        const t = seg.text!.replace(/^ +| +$/g, "");
+        if (t === "") {
+          midSpace = true;
+          continue;
+        }
+        let join = false;
+        if (plainB.length > 0) {
+          const spaced = prevTrail || midSpace || lead;
+          if (sawBreak) join = true;
+          else if (sawPlaceholder) join = spaced && !startsWithBindingPunct(t);
+          else join = spaced;
+        }
+        if (join) plainB += " ";
+        plainB += t;
+        prevTrail = seg.text!.endsWith(" ");
+        sawBreak = false;
+        sawPlaceholder = false;
+        midSpace = false;
+      } else if (seg.kind === "break") {
+        sawBreak = true;
+      } else if (seg.kind === "placeholder") {
+        sawPlaceholder = true;
+      }
+    }
+
+    // Plain text is only worth keeping alongside SSML when it diverges from
+    // what stripping tags from the SSML would produce — i.e. when a
+    // placeholder (an embedded reference) was dropped from it. A pure
+    // formatting/language shift with no embedded objects makes plain text a
+    // redundant, mechanical derivative of the SSML, so it's left out.
+    const hasPlaceholder = segments.some((s) => s.kind === "placeholder");
+    const text: TextBuilder = {
+      plain: needSSML && !hasPlaceholder ? "" : plainB.trim(),
+      ssml: "",
+      language: baseLang,
+    };
+
+    if (needSSML) {
+      let sb = "";
+      for (const seg of segments) {
+        if (seg.kind === "text") {
+          let tag = seg.ctx!.tag;
+          let attrs = seg.ctx!.attrs;
+          if (seg.ctx!.lang !== baseLang && seg.ctx!.lang !== "") {
+            // A language shift takes priority over whatever SSML tag the
+            // shifting element would otherwise map to.
+            tag = "lang";
+            attrs = undefined;
+          }
+          if (tag) {
+            sb += `<${tag}`;
+            for (const [k, v] of Object.entries(attrs ?? {})) {
+              sb += ` ${k}="${ssmlAttrEscape(v)}"`;
+            }
+            if (seg.ctx!.lang !== baseLang && seg.ctx!.lang !== "") {
+              sb += ` xml:lang="${ssmlAttrEscape(seg.ctx!.lang)}"`;
+            }
+            sb += `>${ssmlTextEscape(seg.text!)}</${tag}>`;
+          } else {
+            sb += ssmlTextEscape(seg.text!);
+          }
+        } else if (seg.kind === "break") {
+          sb += "<break/>";
+        } else if (seg.kind === "placeholder") {
+          sb += `<readium:${seg.tag} id="${ssmlAttrEscape(seg.child!.object.id!)}" />`;
+        }
+      }
+      text.ssml = sb;
+    }
+
+    const textObj = new NavObject();
+    textObj.object = { text };
+    for (const child of pending) {
+      textObj.children.push(child);
+    }
+    this.appendChild(textObj);
+  }
+}
+
+/**
+ * Converts the children of an HTML or XHTML fragment or document's <body>
+ * into Guided Navigation objects.
+ */
+export function convert(input: string, mediaType?: GndMediaType): GndNode[] {
+  const mt = mediaType ?? sniffMediaType(input);
+  const doc = new DOMParser().parseFromString(input, mt);
+  const body = doc.querySelector("body");
+  const root = body ?? doc.documentElement;
+
+  const converter = new Converter(mt === "application/xhtml+xml");
+  converter.convertChildren(root);
+  return converter.result();
+}
diff --git a/src/gnd/dom.ts b/src/gnd/dom.ts
new file mode 100644
index 0000000..9edc117
--- /dev/null
+++ b/src/gnd/dom.ts
@@ -0,0 +1,39 @@
+const ELEMENT_NODE = 1;
+
+export function nodeLanguage(el: Element | null): string {
+  for (let n: Element | null = el; n; n = n.parentElement) {
+    const xmlLang = n.getAttribute("xml:lang");
+    if (xmlLang) return xmlLang;
+    const lang = n.getAttribute("lang");
+    if (lang) return lang;
+  }
+  return "";
+}
+
+export function hasElementChild(el: Element): boolean {
+  for (let c = el.firstChild; c; c = c.nextSibling) {
+    if (c.nodeType === ELEMENT_NODE) return true;
+  }
+  return false;
+}
+
+export function isAncestorOf(anc: Element, n: Element): boolean {
+  for (let p: Element | null = n; p; p = p.parentElement) {
+    if (p === anc) return true;
+  }
+  return false;
+}
+
+export type GndMediaType = "text/html" | "application/xhtml+xml";
+
+export function sniffMediaType(input: string): GndMediaType {
+  const head = input.slice(0, 500);
+  if (
+    /<\?xml\b/.test(head) ||
+    /xmlns:epub=/.test(head) ||
+    /DOCTYPE\s+html\s+PUBLIC\s+"-\/\/W3C\/\/DTD XHTML/i.test(head)
+  ) {
+    return "application/xhtml+xml";
+  }
+  return "text/html";
+}
diff --git a/src/gnd/index.ts b/src/gnd/index.ts
index 9047e87..89f6b72 100644
--- a/src/gnd/index.ts
+++ b/src/gnd/index.ts
@@ -1 +1,4 @@
 export type { GndRole, GndTextAlternative, GndNode, GndDocument } from "./types.js";
+export { parseGnd } from "./parseGnd.js";
+export { convert } from "./converter.js";
+export type { GndMediaType } from "./dom.js";
diff --git a/src/gnd/object.ts b/src/gnd/object.ts
new file mode 100644
index 0000000..f415f24
--- /dev/null
+++ b/src/gnd/object.ts
@@ -0,0 +1,122 @@
+import type { GndNode, GndRole } from "./types.js";
+import { type TextBuilder, textIsEmpty, finalizeText } from "./text.js";
+
+export interface ObjBuilder {
+  id?: string;
+  audioref?: string;
+  imgref?: string;
+  textref?: string;
+  videoref?: string;
+  text?: TextBuilder;
+  role?: GndRole[];
+  children?: ObjBuilder[];
+  description?: string;
+}
+
+export function isEmptyObj(o: ObjBuilder): boolean {
+  return (
+    !o.audioref &&
+    !o.imgref &&
+    !o.textref &&
+    !o.videoref &&
+    (!o.text || textIsEmpty(o.text)) &&
+    !(o.children && o.children.length > 0) &&
+    !o.description
+  );
+}
+
+// A transparent wrapper (e.g. a plain <div>) carrying no information of its
+// own besides its children — spliced into the parent's children.
+function isChildrenOnly(o: ObjBuilder): boolean {
+  return (
+    !o.audioref &&
+    !o.imgref &&
+    !o.textref &&
+    !o.videoref &&
+    (!o.text || textIsEmpty(o.text)) &&
+    !!(o.children && o.children.length > 0) &&
+    !(o.role && o.role.length > 0) &&
+    !o.id
+  );
+}
+
+// A lone child with no role/id of its own: its text and refs are hoisted into
+// the parent object directly, e.g. a paragraph wrapping a single plain link
+// becomes {role, text, textref} rather than nesting an anonymous child.
+function isHoistable(o: ObjBuilder): boolean {
+  return !(o.role && o.role.length > 0) && !o.id;
+}
+
+/** A node being built up during the tree walk, before its final shape is known. */
+export class NavObject {
+  el?: Element;
+  object: ObjBuilder = {};
+  children: NavObject[] = [];
+  noText = false;
+
+  finalize(): ObjBuilder {
+    const result = this.object;
+    const finalChildren: ObjBuilder[] = [];
+    for (const child of this.children) {
+      const res = child.finalize();
+      if (isEmptyObj(res)) continue;
+      if (isChildrenOnly(res)) {
+        finalChildren.push(...(res.children ?? []));
+        continue;
+      }
+      finalChildren.push(res);
+    }
+    if (finalChildren.length > 0) result.children = finalChildren;
+
+    // Hoist a lone child with no role/id into the object itself: its text and
+    // refs merge directly into the parent, e.g. a paragraph with a single
+    // plain link becomes {role, text, textref} instead of nesting an
+    // anonymous child.
+    if ((!result.text || textIsEmpty(result.text)) && result.children?.length === 1) {
+      const child = result.children[0];
+      if (isHoistable(child)) {
+        if (child.text) result.text = child.text;
+        if (child.textref) result.textref = child.textref;
+        if (child.imgref) result.imgref = child.imgref;
+        if (child.audioref) result.audioref = child.audioref;
+        if (child.videoref) result.videoref = child.videoref;
+        result.children = child.children;
+      }
+    }
+
+    return result;
+  }
+}
+
+export function finalizeToGndNode(o: ObjBuilder): GndNode {
+  const node: GndNode = {};
+  if (o.id) node.id = o.id;
+  if (o.textref) node.textref = o.textref;
+  if (o.imgref) node.imgref = o.imgref;
+  if (o.audioref) node.audioref = o.audioref;
+  if (o.videoref) node.videoref = o.videoref;
+  const text = finalizeText(o.text);
+  if (text !== undefined) node.text = text;
+  if (o.role && o.role.length > 0) node.role = o.role;
+  if (o.children && o.children.length > 0) node.children = o.children.map(finalizeToGndNode);
+  if (o.description) node.description = o.description;
+  return node;
+}
+
+export function gndNodeToObjBuilder(n: GndNode): ObjBuilder {
+  const o: ObjBuilder = {};
+  if (n.id) o.id = n.id;
+  if (n.textref) o.textref = n.textref;
+  if (n.imgref) o.imgref = n.imgref;
+  if (n.audioref) o.audioref = n.audioref;
+  if (n.videoref) o.videoref = n.videoref;
+  if (n.role) o.role = n.role;
+  if (n.description) o.description = n.description;
+  if (typeof n.text === "string") {
+    o.text = { plain: n.text, ssml: "", language: "" };
+  } else if (n.text) {
+    o.text = { plain: n.text.plain ?? "", ssml: n.text.ssml ?? "", language: n.text.language };
+  }
+  if (n.children) o.children = n.children.map(gndNodeToObjBuilder);
+  return o;
+}
diff --git a/src/gnd/parseGnd.ts b/src/gnd/parseGnd.ts
new file mode 100644
index 0000000..3270568
--- /dev/null
+++ b/src/gnd/parseGnd.ts
@@ -0,0 +1,16 @@
+import type { GndDocument } from "./types.js";
+import { convert } from "./converter.js";
+import type { GndMediaType } from "./dom.js";
+
+export type { GndMediaType };
+
+/**
+ * Parses an HTML or XHTML fragment or document into a Guided Navigation
+ * document, following https://github.com/readium/guided-navigation.
+ */
+export function parseGnd(input: string, mediaType?: GndMediaType): GndDocument {
+  const children = convert(input, mediaType);
+  const body: GndDocument["guided"][number] = { role: ["body"] };
+  if (children.length > 0) body.children = children;
+  return { guided: [body] };
+}
diff --git a/src/gnd/roles.ts b/src/gnd/roles.ts
new file mode 100644
index 0000000..8139bbf
--- /dev/null
+++ b/src/gnd/roles.ts
@@ -0,0 +1,258 @@
+import type { GndRole } from "./types.js";
+
+// https://github.com/readium/guided-navigation/blob/main/schema/roles.schema.json
+// `sequence` is intentionally omitted: it has no documented HTML/ARIA/epub:type
+// mapping anywhere in the spec or its examples.
+
+const headingRoles: GndRole[] = [
+  "heading1",
+  "heading2",
+  "heading3",
+  "heading4",
+  "heading5",
+  "heading6",
+];
+
+const ariaRoles: Record<string, GndRole> = {
+  "doc-abstract": "abstract",
+  "doc-acknowledgments": "acknowledgments",
+  "doc-afterword": "afterword",
+  "doc-appendix": "appendix",
+  article: "article",
+  "doc-backlink": "backlink",
+  "doc-bibliography": "bibliography",
+  "doc-biblioref": "biblioref",
+  blockquote: "blockquote",
+  caption: "caption",
+  cell: "cell",
+  "doc-chapter": "chapter",
+  "doc-colophon": "colophon",
+  columnheader: "columnheader",
+  complementary: "complementary",
+  "doc-conclusion": "conclusion",
+  "doc-cover": "cover",
+  "doc-credit": "credit",
+  "doc-credits": "credits",
+  "doc-dedication": "dedication",
+  definition: "definition",
+  "doc-endnote": "footnote", // Deprecated in DPUB-ARIA 1.1
+  "doc-endnotes": "endnotes",
+  "doc-epigraph": "epigraph",
+  "doc-epilogue": "epilogue",
+  "doc-errata": "errata",
+  "doc-example": "example",
+  figure: "figure",
+  "doc-footnote": "footnote",
+  "doc-foreword": "foreword",
+  "doc-glossary": "glossary",
+  "doc-glossref": "glossref",
+  img: "image",
+  image: "image", // ARIA 1.3 synonym of img
+  "doc-index": "index",
+  "doc-introduction": "introduction",
+  list: "list",
+  listitem: "listItem",
+  main: "main",
+  math: "math",
+  navigation: "navigation",
+  "doc-noteref": "noteref",
+  "doc-notice": "notice",
+  "doc-pagebreak": "pagebreak",
+  "doc-pagelist": "pagelist",
+  paragraph: "paragraph",
+  "doc-part": "part",
+  "doc-preface": "preface",
+  "doc-prologue": "prologue",
+  "doc-pullquote": "pullquote",
+  presentation: "presentation",
+  none: "presentation",
+  "doc-qna": "qna",
+  qna: "qna",
+  region: "region",
+  row: "row",
+  rowheader: "rowheader",
+  separator: "separator",
+  "doc-subtitle": "subtitle",
+  table: "table",
+  term: "term",
+  "doc-tip": "tip",
+  "doc-toc": "toc",
+};
+
+const epubTypeRoles: Record<string, GndRole> = {
+  abstract: "abstract",
+  acknowledgments: "acknowledgments",
+  afterword: "afterword",
+  appendix: "appendix",
+  aside: "aside",
+  backlink: "backlink",
+  bibliography: "bibliography",
+  biblioref: "biblioref",
+  "table-cell": "cell",
+  chapter: "chapter",
+  colophon: "colophon",
+  conclusion: "conclusion",
+  cover: "cover",
+  credit: "credit",
+  credits: "credits",
+  dedication: "dedication",
+  glossdef: "definition",
+  endnote: "footnote",
+  endnotes: "endnotes",
+  rearnote: "footnote", // Deprecated alias of endnote
+  rearnotes: "endnotes", // Deprecated alias of endnotes
+  epigraph: "epigraph",
+  epilogue: "epilogue",
+  errata: "errata",
+  example: "example",
+  figure: "figure",
+  footnote: "footnote",
+  foreword: "foreword",
+  glossary: "glossary",
+  glossref: "glossref",
+  index: "index",
+  introduction: "introduction",
+  landmarks: "landmarks",
+  list: "list",
+  "list-item": "listItem",
+  loa: "loa",
+  loi: "loi",
+  lot: "lot",
+  lov: "lov",
+  noteref: "noteref",
+  notice: "notice",
+  pagebreak: "pagebreak",
+  "page-list": "pagelist",
+  pagelist: "pagelist",
+  part: "part",
+  preface: "preface",
+  prologue: "prologue",
+  pullquote: "pullquote",
+  qna: "qna",
+  "table-row": "row",
+  subtitle: "subtitle",
+  table: "table",
+  glossterm: "term",
+  tip: "tip",
+  toc: "toc",
+};
+
+// Elements whose role depends only on their tag name.
+const simpleElementTypeRoles: Record<string, GndRole> = {
+  article: "article",
+  aside: "aside",
+  audio: "audio",
+  blockquote: "blockquote",
+  caption: "caption",
+  figcaption: "caption",
+  td: "cell",
+  dd: "definition",
+  details: "details",
+  figure: "figure",
+  header: "header",
+  h1: "heading1",
+  h2: "heading2",
+  h3: "heading3",
+  h4: "heading4",
+  h5: "heading5",
+  h6: "heading6",
+  img: "image",
+  ul: "list",
+  ol: "list",
+  li: "listItem",
+  main: "main",
+  math: "math",
+  nav: "navigation",
+  p: "paragraph",
+  pre: "preformatted",
+  tr: "row",
+  section: "section",
+  hr: "separator",
+  summary: "summary",
+  table: "table",
+  dfn: "term",
+  dt: "term",
+  video: "video",
+  svg: "image",
+};
+
+/**
+ * Determines the Guided Navigation roles of an element, combining the roles
+ * derived from the element type itself with the ones from its ARIA `role` and
+ * `epub:type` attributes, e.g. `<section epub:type="chapter">` -> `[section, chapter]`.
+ * An ARIA role of "presentation"/"none" strips the element of its native semantics.
+ */
+export function extractNodeRoles(el: Element): GndRole[] {
+  const roles: GndRole[] = [];
+  const add = (role: GndRole) => {
+    if (!roles.includes(role)) roles.push(role);
+  };
+
+  const attrRoles: GndRole[] = [];
+  let presentational = false;
+
+  const role = el.getAttribute("role");
+  if (role) {
+    for (const val of role.split(/\s+/).filter(Boolean)) {
+      if (val === "presentation" || val === "none") {
+        presentational = true;
+      }
+      if (val === "heading") {
+        // The heading level comes from aria-level. It defaults to 2:
+        // https://www.w3.org/TR/wai-aria/#heading
+        let level = 2;
+        const ariaLevel = parseInt(el.getAttribute("aria-level") ?? "", 10);
+        if (Number.isFinite(ariaLevel) && ariaLevel >= 1) {
+          level = Math.min(ariaLevel, 6);
+        }
+        attrRoles.push(headingRoles[level - 1]);
+      } else if (ariaRoles[val]) {
+        attrRoles.push(ariaRoles[val]);
+      }
+    }
+  }
+
+  // epub:type is only meaningful (and only ever set) in XHTML documents with
+  // the epub namespace declared; read the literal attribute name rather than
+  // resolving the namespace, since XHTML documents always use the "epub"
+  // prefix in practice.
+  const epubType = el.getAttribute("epub:type");
+  if (epubType) {
+    for (const val of epubType.split(/\s+/).filter(Boolean)) {
+      const mapped = epubTypeRoles[val];
+      if (mapped) attrRoles.push(mapped);
+    }
+  }
+
+  if (presentational) {
+    // The element only retains the presentation role
+    return ["presentation"];
+  }
+
+  // Based on element type. The element's own role comes first, followed by the
+  // more specific attribute-based roles, matching the ordering of the examples
+  // in the Guided Navigation specification.
+  const tagName = el.tagName.toLowerCase();
+  if (tagName === "body") {
+    add("body");
+  } else if (tagName === "th") {
+    switch (el.getAttribute("scope")) {
+      case "col":
+        add("columnheader");
+        break;
+      case "row":
+        add("rowheader");
+        break;
+      default:
+        // Without an explicit scope the direction is unknown, but it's still a cell
+        add("cell");
+    }
+  } else {
+    const mapped = simpleElementTypeRoles[tagName];
+    if (mapped) add(mapped);
+  }
+
+  for (const r of attrRoles) add(r);
+
+  return roles;
+}
diff --git a/src/gnd/text.ts b/src/gnd/text.ts
new file mode 100644
index 0000000..5a0130d
--- /dev/null
+++ b/src/gnd/text.ts
@@ -0,0 +1,62 @@
+import type { GndTextAlternative } from "./types.js";
+
+export interface TextBuilder {
+  plain: string;
+  ssml: string;
+  language: string;
+}
+
+export function textIsEmpty(t: TextBuilder): boolean {
+  return t.plain === "" && t.ssml === "" && t.language === "";
+}
+
+export function finalizeText(t?: TextBuilder): string | GndTextAlternative | undefined {
+  if (!t || textIsEmpty(t)) return undefined;
+  if (t.ssml === "" && t.language === "") return t.plain;
+  const alt: GndTextAlternative = { language: t.language };
+  if (t.plain !== "") alt.plain = t.plain;
+  if (t.ssml !== "") alt.ssml = t.ssml;
+  return alt;
+}
+
+export interface SSMLContext {
+  lang: string;
+  tag: string;
+  attrs?: Record<string, string>;
+}
+
+export function ctxEqual(a: SSMLContext, b: SSMLContext): boolean {
+  if (a.lang !== b.lang || a.tag !== b.tag) return false;
+  const ae = Object.entries(a.attrs ?? {});
+  const be = Object.entries(b.attrs ?? {});
+  if (ae.length !== be.length) return false;
+  return ae.every(([k, v]) => b.attrs?.[k] === v);
+}
+
+export const ssmlTextEscape = (s: string) =>
+  s.replace(/&/g, "&amp;").replace(/</g, "&lt;").replace(/>/g, "&gt;");
+export const ssmlAttrEscape = (s: string) =>
+  s.replace(/&/g, "&amp;").replace(/</g, "&lt;").replace(/>/g, "&gt;").replace(/"/g, "&quot;");
+
+export function startsWithBindingPunct(s: string): boolean {
+  return /^[.,;:!?)\]}]/.test(s);
+}
+
+export function normalizeWhitespace(text: string, stripLeading: boolean): string {
+  let out = "";
+  let lastWasWhite = false;
+  let reachedNonWhite = false;
+  for (const ch of text) {
+    if (/\s/.test(ch)) {
+      if ((stripLeading && !reachedNonWhite) || lastWasWhite) continue;
+      out += " ";
+      lastWasWhite = true;
+    } else if (ch !== "​" && ch !== "­") {
+      // zero width space, soft hyphen
+      out += ch;
+      lastWasWhite = false;
+      reachedNonWhite = true;
+    }
+  }
+  return out;
+}
diff --git a/src/gnd/types.ts b/src/gnd/types.ts
index 149c71b..76fe337 100644
--- a/src/gnd/types.ts
+++ b/src/gnd/types.ts
@@ -30,7 +30,11 @@ export interface GndNode {
   children?: GndNode[];
 }
 
-// TODO: root shape (single node vs. an implicit multi-node fragment) is not
-// yet settled upstream; fixtures with multiple top-level siblings currently
-// use a bare `{ children: GndNode[] }` with no role.
-export type GndDocument = GndNode;
+// A Guided Navigation Document — https://readium.org/guided-navigation/schema/document.schema.json
+// Always a complete document: `guided` holds every top-level item produced
+// from the input, however many there are (one item, several siblings, or —
+// for a piece of input that describes no navigable content at all — none).
+export interface GndDocument {
+  links?: unknown[];
+  guided: GndNode[];
+}
diff --git a/src/index.ts b/src/index.ts
index e437893..eba65d0 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -9,4 +9,5 @@ export * from "./voices/types";
 export * from "./engine";
 export * from "./navigator";
 export * from "./provider";
-export * from "./utterance";
\ No newline at end of file
+export * from "./utterance";
+export * from "./gnd";
\ No newline at end of file
diff --git a/test/gnd/fixtures.test.ts b/test/gnd/fixtures.test.ts
index 4a48d10..bd5cbd1 100644
--- a/test/gnd/fixtures.test.ts
+++ b/test/gnd/fixtures.test.ts
@@ -1,5 +1,7 @@
+import "./setup.js";
 import test from "ava";
 import { loadManifest, loadFixture } from "../testUtils.js";
+import { convert } from "../../src/gnd/converter.js";
 
 const manifest = loadManifest();
 
@@ -13,6 +15,39 @@ test("manifest has no duplicate ids", (t) => {
   t.is(new Set(ids).size, ids.length);
 });
 
+function sortKeysDeep(value: unknown): unknown {
+  if (Array.isArray(value)) return value.map(sortKeysDeep);
+  if (value && typeof value === "object") {
+    return Object.keys(value)
+      .sort()
+      .reduce((acc: Record<string, unknown>, key) => {
+        acc[key] = sortKeysDeep((value as Record<string, unknown>)[key]);
+        return acc;
+      }, {});
+  }
+  return value;
+}
+
+// gnd.json stores a single fixture's expected top-level item(s) directly —
+// a bare object for one item, or a role-less/id-less `{children: [...]}` for
+// several siblings — while `convert()` always returns an array. This maps
+// the stored file format onto that array shape for comparison.
+function expectedTopLevel(gnd: unknown): unknown[] {
+  if (gnd && typeof gnd === "object" && !Array.isArray(gnd)) {
+    const keys = Object.keys(gnd);
+    if (keys.length === 1 && keys[0] === "children") {
+      return (gnd as { children: unknown[] }).children;
+    }
+  }
+  return [gnd];
+}
+
+// <body> is always the traversal root, never content in its own right, so
+// convert() never produces a "body"-rolebearing object for it to check
+// against — this fixture documents the expected role mapping but can't be
+// exercised through convert(); it's excluded from that check only.
+const excludedFromConvertCheck = new Set(["body-html-native"]);
+
 for (const entry of manifest) {
   test(`fixture "${entry.id}": loads and has the expected shape`, (t) => {
     t.is(entry.dir, entry.id);
@@ -35,4 +70,12 @@ for (const entry of manifest) {
       t.true(typeof utterance.text === "string", "each utterance needs a text field");
     }
   });
+
+  if (!excludedFromConvertCheck.has(entry.id)) {
+    test(`fixture "${entry.id}": convert matches gnd.json`, (t) => {
+      const fixture = loadFixture(entry.id);
+      const actual = convert(fixture.inputHtml);
+      t.deepEqual(sortKeysDeep(actual), sortKeysDeep(expectedTopLevel(fixture.gnd)));
+    });
+  }
 }
diff --git a/test/gnd/setup.ts b/test/gnd/setup.ts
new file mode 100644
index 0000000..709e4e8
--- /dev/null
+++ b/test/gnd/setup.ts
@@ -0,0 +1,27 @@
+import { DOMParser as LinkedomDOMParser } from "linkedom";
+
+// ava runs tests under Node, which has no native DOMParser — polyfill it here
+// for tests only. src/gnd/* must never import linkedom directly; it targets
+// the browser's native DOMParser.
+//
+// Unlike a real browser, linkedom doesn't perform full HTML5 tree
+// construction for a bare fragment with no <body> tag at all (documentElement
+// ends up being the fragment's own top-level element instead of a proper
+// <html><body>...</body></html>). Real browsers always construct the full
+// document regardless of how partial the input is. This wraps the input in
+// <body> first so linkedom sees a real body tag to build around, matching
+// what a real DOMParser would produce.
+class TestDOMParser {
+  private inner = new LinkedomDOMParser();
+
+  parseFromString(input: string, mimeType: DOMParserSupportedType) {
+    if (mimeType === "text/html" && !/<body[\s>]/i.test(input)) {
+      input = `<body>${input}</body>`;
+    }
+    return (this.inner.parseFromString as (i: string, m: string) => Document)(input, mimeType);
+  }
+}
+
+if (typeof globalThis.DOMParser === "undefined") {
+  (globalThis as any).DOMParser = TestDOMParser;
+}

From 48cf66e231c0c67acff1096e3638ad9a0e568a05 Mon Sep 17 00:00:00 2001
From: Jiminy Panoz <JayPanoz@users.noreply.github.com>
Date: Fri, 10 Jul 2026 10:03:12 +0200
Subject: [PATCH 5/7] Update pagebreak fixtures

---
 fixtures/manifest.json                       |  4 ++--
 fixtures/pagebreak-epub-type/gnd.json        | 23 +++++++++++++-------
 fixtures/pagebreak-epub-type/input.html      |  5 ++---
 fixtures/pagebreak-epub-type/meta.json       |  2 +-
 fixtures/pagebreak-epub-type/utterances.json |  6 ++---
 fixtures/pagebreak-role-aria/gnd.json        | 23 +++++++++++++-------
 fixtures/pagebreak-role-aria/input.html      |  5 ++---
 fixtures/pagebreak-role-aria/meta.json       |  2 +-
 fixtures/pagebreak-role-aria/utterances.json |  6 ++---
 9 files changed, 44 insertions(+), 32 deletions(-)

diff --git a/fixtures/manifest.json b/fixtures/manifest.json
index d81437d..11518fb 100644
--- a/fixtures/manifest.json
+++ b/fixtures/manifest.json
@@ -971,7 +971,7 @@
     "id": "pagebreak-epub-type",
     "dir": "pagebreak-epub-type",
     "role": "pagebreak",
-    "description": "A standalone pagebreak between two paragraphs, via epub:type=\"pagebreak\"",
+    "description": "A standalone pagebreak and one falling in the middle of a sentence, via epub:type=\"pagebreak\"",
     "files": {
       "input": "input.html",
       "gnd": "gnd.json",
@@ -982,7 +982,7 @@
     "id": "pagebreak-role-aria",
     "dir": "pagebreak-role-aria",
     "role": "pagebreak",
-    "description": "A standalone pagebreak between two paragraphs, via role=\"doc-pagebreak\"",
+    "description": "A standalone pagebreak and one falling in the middle of a sentence, via role=\"doc-pagebreak\"",
     "files": {
       "input": "input.html",
       "gnd": "gnd.json",
diff --git a/fixtures/pagebreak-epub-type/gnd.json b/fixtures/pagebreak-epub-type/gnd.json
index 3397c22..22150a2 100644
--- a/fixtures/pagebreak-epub-type/gnd.json
+++ b/fixtures/pagebreak-epub-type/gnd.json
@@ -1,22 +1,29 @@
 {
   "children": [
-    {
-      "role": [
-        "paragraph"
-      ],
-      "text": "End of the previous page."
-    },
     {
       "role": [
         "pagebreak"
       ],
-      "text": "5"
+      "text": "4"
     },
     {
       "role": [
         "paragraph"
       ],
-      "text": "Start of the next page."
+      "text": {
+        "plain": "And the next pagebreak is in the middle of a sentence.",
+        "ssml": "And the next pagebreak is in the middle <readium:pagebreak id=\"pagebreak1\" /> of a sentence.",
+        "language": "en"
+      },
+      "children": [
+        {
+          "role": [
+            "pagebreak"
+          ],
+          "id": "pagebreak1",
+          "text": "5"
+        }
+      ]
     }
   ]
 }
diff --git a/fixtures/pagebreak-epub-type/input.html b/fixtures/pagebreak-epub-type/input.html
index bf43c2c..eff78dc 100644
--- a/fixtures/pagebreak-epub-type/input.html
+++ b/fixtures/pagebreak-epub-type/input.html
@@ -6,8 +6,7 @@
 <title>Fixture</title>
 </head>
 <body>
-<p>End of the previous page.</p>
-<span epub:type="pagebreak" title="5"></span>
-<p>Start of the next page.</p>
+<span epub:type="pagebreak" title="4"></span>
+<p>And the next pagebreak is in the middle <span epub:type="pagebreak" title="5"></span> of a sentence.</p>
 </body>
 </html>
diff --git a/fixtures/pagebreak-epub-type/meta.json b/fixtures/pagebreak-epub-type/meta.json
index 7b2a104..bdf0f44 100644
--- a/fixtures/pagebreak-epub-type/meta.json
+++ b/fixtures/pagebreak-epub-type/meta.json
@@ -1,6 +1,6 @@
 {
   "id": "pagebreak-epub-type",
-  "description": "A standalone pagebreak between two paragraphs, via epub:type=\"pagebreak\"",
+  "description": "A standalone pagebreak and one falling in the middle of a sentence, via epub:type=\"pagebreak\"",
   "role": "pagebreak",
   "rolesCovered": [
     "pagebreak"
diff --git a/fixtures/pagebreak-epub-type/utterances.json b/fixtures/pagebreak-epub-type/utterances.json
index 328b01a..9f6ab57 100644
--- a/fixtures/pagebreak-epub-type/utterances.json
+++ b/fixtures/pagebreak-epub-type/utterances.json
@@ -1,11 +1,11 @@
 [
   {
-    "text": "End of the previous page."
+    "text": "Pagebreak. Page: 4."
   },
   {
-    "text": "Pagebreak. Page: 5."
+    "text": "And the next pagebreak is in the middle of a sentence."
   },
   {
-    "text": "Start of the next page."
+    "text": "Pagebreak. Page: 5."
   }
 ]
diff --git a/fixtures/pagebreak-role-aria/gnd.json b/fixtures/pagebreak-role-aria/gnd.json
index 3397c22..22150a2 100644
--- a/fixtures/pagebreak-role-aria/gnd.json
+++ b/fixtures/pagebreak-role-aria/gnd.json
@@ -1,22 +1,29 @@
 {
   "children": [
-    {
-      "role": [
-        "paragraph"
-      ],
-      "text": "End of the previous page."
-    },
     {
       "role": [
         "pagebreak"
       ],
-      "text": "5"
+      "text": "4"
     },
     {
       "role": [
         "paragraph"
       ],
-      "text": "Start of the next page."
+      "text": {
+        "plain": "And the next pagebreak is in the middle of a sentence.",
+        "ssml": "And the next pagebreak is in the middle <readium:pagebreak id=\"pagebreak1\" /> of a sentence.",
+        "language": "en"
+      },
+      "children": [
+        {
+          "role": [
+            "pagebreak"
+          ],
+          "id": "pagebreak1",
+          "text": "5"
+        }
+      ]
     }
   ]
 }
diff --git a/fixtures/pagebreak-role-aria/input.html b/fixtures/pagebreak-role-aria/input.html
index 3152fb0..4c25894 100644
--- a/fixtures/pagebreak-role-aria/input.html
+++ b/fixtures/pagebreak-role-aria/input.html
@@ -1,3 +1,2 @@
-<p>End of the previous page.</p>
-<span role="doc-pagebreak" title="5"></span>
-<p>Start of the next page.</p>
+<span role="doc-pagebreak" title="4"></span>
+<p>And the next pagebreak is in the middle <span role="doc-pagebreak" title="5"></span> of a sentence.</p>
diff --git a/fixtures/pagebreak-role-aria/meta.json b/fixtures/pagebreak-role-aria/meta.json
index 01c1759..c31359f 100644
--- a/fixtures/pagebreak-role-aria/meta.json
+++ b/fixtures/pagebreak-role-aria/meta.json
@@ -1,6 +1,6 @@
 {
   "id": "pagebreak-role-aria",
-  "description": "A standalone pagebreak between two paragraphs, via role=\"doc-pagebreak\"",
+  "description": "A standalone pagebreak and one falling in the middle of a sentence, via role=\"doc-pagebreak\"",
   "role": "pagebreak",
   "rolesCovered": [
     "pagebreak"
diff --git a/fixtures/pagebreak-role-aria/utterances.json b/fixtures/pagebreak-role-aria/utterances.json
index 328b01a..9f6ab57 100644
--- a/fixtures/pagebreak-role-aria/utterances.json
+++ b/fixtures/pagebreak-role-aria/utterances.json
@@ -1,11 +1,11 @@
 [
   {
-    "text": "End of the previous page."
+    "text": "Pagebreak. Page: 4."
   },
   {
-    "text": "Pagebreak. Page: 5."
+    "text": "And the next pagebreak is in the middle of a sentence."
   },
   {
-    "text": "Start of the next page."
+    "text": "Pagebreak. Page: 5."
   }
 ]

From 5d524a365c870eb134acd48393d20cd699b5a1d7 Mon Sep 17 00:00:00 2001
From: Jiminy Panoz <JayPanoz@users.noreply.github.com>
Date: Fri, 10 Jul 2026 18:02:11 +0200
Subject: [PATCH 6/7] utterance extraction

---
 demo/playground/script.js                     |  36 ++++--
 fixtures/README.md                            |  43 ++++++-
 fixtures/ROLES_COVERAGE.md                    |   4 +-
 fixtures/abstract-epub-type/utterances.json   |   2 +-
 fixtures/abstract-role-aria/utterances.json   |   2 +-
 .../acknowledgments-epub-type/utterances.json |   2 +-
 .../acknowledgments-role-aria/utterances.json |   2 +-
 fixtures/afterword-epub-type/utterances.json  |   2 +-
 fixtures/afterword-role-aria/utterances.json  |   2 +-
 fixtures/appendix-epub-type/utterances.json   |   2 +-
 fixtures/appendix-role-aria/utterances.json   |   2 +-
 fixtures/article-html-native/utterances.json  |   2 +-
 fixtures/aside-html-native/meta.json          |   3 +-
 .../aside-html-native/utterances-skipped.json |   1 +
 fixtures/aside-html-native/utterances.json    |   2 +-
 fixtures/audio-html-native/utterances.json    |   2 +-
 fixtures/backlink-epub-type/utterances.json   |   2 +-
 fixtures/backlink-role-aria/utterances.json   |   2 +-
 .../bibliography-epub-type/utterances.json    |   4 +-
 .../bibliography-role-aria/utterances.json    |   4 +-
 fixtures/biblioref-epub-type/utterances.json  |   2 +-
 fixtures/biblioref-role-aria/utterances.json  |   2 +-
 .../blockquote-html-native/utterances.json    |   2 +-
 fixtures/body-html-native/utterances.json     |   2 +-
 fixtures/chapter-epub-type/utterances.json    |   2 +-
 fixtures/chapter-role-aria/utterances.json    |   2 +-
 fixtures/colophon-epub-type/utterances.json   |   2 +-
 fixtures/colophon-role-aria/utterances.json   |   2 +-
 .../complementary-role-aria/utterances.json   |   2 +-
 fixtures/conclusion-epub-type/utterances.json |   2 +-
 fixtures/conclusion-role-aria/utterances.json |   2 +-
 fixtures/cover-epub-type/utterances.json      |   2 +-
 fixtures/cover-role-aria/utterances.json      |   2 +-
 fixtures/credit-epub-type/utterances.json     |   2 +-
 fixtures/credit-role-aria/utterances.json     |   2 +-
 fixtures/credits-epub-type/utterances.json    |   4 +-
 fixtures/credits-role-aria/utterances.json    |   4 +-
 fixtures/dedication-epub-type/utterances.json |   2 +-
 fixtures/dedication-role-aria/utterances.json |   2 +-
 fixtures/definition-epub-type/utterances.json |   2 +-
 .../definition-html-native/utterances.json    |   2 +-
 fixtures/definition-role-aria/utterances.json |   2 +-
 fixtures/details-html-native/utterances.json  |   2 +-
 fixtures/endnotes-epub-type/utterances.json   |   4 +-
 fixtures/endnotes-role-aria/utterances.json   |   4 +-
 fixtures/epigraph-epub-type/utterances.json   |   2 +-
 fixtures/epigraph-role-aria/utterances.json   |   2 +-
 fixtures/epilogue-epub-type/utterances.json   |   2 +-
 fixtures/epilogue-role-aria/utterances.json   |   2 +-
 fixtures/errata-epub-type/utterances.json     |   2 +-
 fixtures/errata-role-aria/utterances.json     |   2 +-
 fixtures/example-epub-type/utterances.json    |   2 +-
 fixtures/example-role-aria/utterances.json    |   2 +-
 .../figure-basic-epub-type/utterances.json    |   2 +-
 .../figure-basic-html-native/utterances.json  |   2 +-
 .../figure-basic-role-aria/utterances.json    |   2 +-
 .../utterances.json                           |   2 +-
 .../figure-caption-role-aria/utterances.json  |   2 +-
 fixtures/figure-describedby/utterances.json   |   5 +-
 fixtures/footnote-epub-type/meta.json         |   3 +-
 .../utterances-skipped.json                   |   6 +
 fixtures/footnote-epub-type/utterances.json   |  11 +-
 fixtures/footnote-role-aria/meta.json         |   3 +-
 .../utterances-skipped.json                   |   6 +
 fixtures/footnote-role-aria/utterances.json   |  11 +-
 fixtures/foreword-epub-type/utterances.json   |   2 +-
 fixtures/foreword-role-aria/utterances.json   |   2 +-
 fixtures/glossary-epub-type/utterances.json   |   8 +-
 fixtures/glossary-role-aria/utterances.json   |   8 +-
 fixtures/glossref-epub-type/utterances.json   |   2 +-
 fixtures/glossref-role-aria/utterances.json   |   2 +-
 fixtures/header-html-native/utterances.json   |   2 +-
 fixtures/heading-html-native/utterances.json  |  12 +-
 fixtures/heading-role-aria/utterances.json    |  12 +-
 .../image-alt-html-native/utterances.json     |   2 +-
 .../utterances.json                           |   4 +-
 .../utterances.json                           |   4 +-
 fixtures/image-role-aria/utterances.json      |   2 +-
 fixtures/index-epub-type/utterances.json      |   4 +-
 fixtures/index-role-aria/utterances.json      |   4 +-
 .../introduction-epub-type/utterances.json    |   2 +-
 .../introduction-role-aria/utterances.json    |   2 +-
 fixtures/landmarks-epub-type/utterances.json  |   6 +-
 fixtures/list-html-native/utterances.json     |   6 +-
 fixtures/list-role-aria/utterances.json       |   6 +-
 fixtures/loa-epub-type/utterances.json        |   4 +-
 fixtures/loi-epub-type/utterances.json        |   4 +-
 fixtures/lot-epub-type/utterances.json        |   4 +-
 fixtures/lov-epub-type/utterances.json        |   4 +-
 fixtures/main-html-native/utterances.json     |   2 +-
 fixtures/main-role-aria/utterances.json       |   2 +-
 fixtures/manifest.json                        | 106 ++++++++++++++++--
 fixtures/math-html-native/utterances.json     |   2 +-
 fixtures/math-role-aria/utterances.json       |   2 +-
 .../navigation-html-native/utterances.json    |   2 +-
 fixtures/navigation-role-aria/utterances.json |   2 +-
 fixtures/notice-epub-type/utterances.json     |   2 +-
 fixtures/notice-role-aria/utterances.json     |   2 +-
 fixtures/pagebreak-epub-type/meta.json        |   3 +-
 .../utterances-skipped.json                   |   6 +
 fixtures/pagebreak-epub-type/utterances.json  |  13 ++-
 fixtures/pagebreak-role-aria/meta.json        |   3 +-
 .../utterances-skipped.json                   |   6 +
 fixtures/pagebreak-role-aria/utterances.json  |  13 ++-
 fixtures/pagelist-epub-type/utterances.json   |   6 +-
 fixtures/pagelist-role-aria/utterances.json   |   6 +-
 fixtures/paragraph-basic/utterances.json      |   2 +-
 .../paragraph-block-level-language/gnd.json   |  22 ++++
 .../paragraph-block-level-language/input.html |  11 ++
 .../paragraph-block-level-language/meta.json  |  10 ++
 .../utterances.json                           |  10 ++
 fixtures/paragraph-document-language/gnd.json |   9 ++
 .../paragraph-document-language/input.html    |  10 ++
 .../paragraph-document-language/meta.json     |  10 ++
 .../utterances.json                           |   6 +
 .../gnd.json                                  |   9 ++
 .../input.html                                |   1 +
 .../meta.json                                 |  10 ++
 .../utterances.json                           |   6 +
 .../paragraph-multilingual-nested/gnd.json    |   9 ++
 .../paragraph-multilingual-nested/input.html  |   1 +
 .../paragraph-multilingual-nested/meta.json   |  10 ++
 .../utterances.json                           |   6 +
 .../gnd.json                                  |   9 ++
 .../input.html                                |   1 +
 .../meta.json                                 |  10 ++
 .../utterances.json                           |   6 +
 .../utterances.json                           |   3 +-
 .../gnd.json                                  |   9 ++
 .../input.html                                |   1 +
 .../meta.json                                 |  10 ++
 .../utterances.json                           |   6 +
 fixtures/part-epub-type/utterances.json       |   2 +-
 fixtures/part-role-aria/utterances.json       |   2 +-
 fixtures/preface-epub-type/utterances.json    |   2 +-
 fixtures/preface-role-aria/utterances.json    |   2 +-
 .../preformatted-html-native/utterances.json  |   2 +-
 .../presentation-role-aria/utterances.json    |   2 +-
 fixtures/prologue-epub-type/utterances.json   |   2 +-
 fixtures/prologue-role-aria/utterances.json   |   2 +-
 fixtures/pullquote-epub-type/utterances.json  |   2 +-
 fixtures/pullquote-role-aria/utterances.json  |   2 +-
 fixtures/qna-epub-type/utterances.json        |   2 +-
 fixtures/qna-role-aria/utterances.json        |   2 +-
 fixtures/region-role-aria/utterances.json     |   2 +-
 fixtures/section-html-native/utterances.json  |   2 +-
 .../separator-html-native/utterances.json     |   4 +-
 fixtures/separator-role-aria/utterances.json  |   4 +-
 fixtures/subtitle-epub-type/utterances.json   |   2 +-
 fixtures/subtitle-role-aria/utterances.json   |   2 +-
 fixtures/summary-html-native/utterances.json  |   2 +-
 fixtures/table-html-native/utterances.json    |  12 +-
 fixtures/table-role-aria/utterances.json      |  12 +-
 fixtures/term-epub-type/utterances.json       |   2 +-
 fixtures/term-html-native/utterances.json     |   2 +-
 fixtures/term-role-aria/utterances.json       |   2 +-
 fixtures/tip-epub-type/utterances.json        |   2 +-
 fixtures/tip-role-aria/utterances.json        |   2 +-
 fixtures/toc-epub-type/utterances.json        |   6 +-
 fixtures/toc-role-aria/utterances.json        |   6 +-
 fixtures/video-html-native/utterances.json    |   2 +-
 package.json                                  |   1 +
 scripts/build-fixtures-manifest.js            |  10 +-
 src/WebSpeech/webSpeechEngine.ts              |  13 ++-
 src/gnd/converter.ts                          |   2 +-
 src/gnd/index.ts                              |   4 +-
 src/gnd/{parseGnd.ts => makeGnd.ts}           |   8 +-
 src/index.ts                                  |   3 +-
 src/utterance.ts                              |   8 +-
 src/utterances/announcements.ts               |  12 ++
 src/utterances/extractUtterances.ts           |  98 ++++++++++++++++
 src/utterances/index.ts                       |   3 +
 src/utterances/roles.ts                       |  26 +++++
 src/utterances/text.ts                        |  79 +++++++++++++
 src/utterances/types.ts                       |  27 +++++
 test/gnd/fixtures.test.ts                     |  17 +--
 test/testUtils.ts                             |   9 +-
 test/utterances/fixtures.test.ts              |  38 +++++++
 test/utterances/skip.test.ts                  |  28 +++++
 179 files changed, 964 insertions(+), 245 deletions(-)
 create mode 100644 fixtures/aside-html-native/utterances-skipped.json
 create mode 100644 fixtures/footnote-epub-type/utterances-skipped.json
 create mode 100644 fixtures/footnote-role-aria/utterances-skipped.json
 create mode 100644 fixtures/pagebreak-epub-type/utterances-skipped.json
 create mode 100644 fixtures/pagebreak-role-aria/utterances-skipped.json
 create mode 100644 fixtures/paragraph-block-level-language/gnd.json
 create mode 100644 fixtures/paragraph-block-level-language/input.html
 create mode 100644 fixtures/paragraph-block-level-language/meta.json
 create mode 100644 fixtures/paragraph-block-level-language/utterances.json
 create mode 100644 fixtures/paragraph-document-language/gnd.json
 create mode 100644 fixtures/paragraph-document-language/input.html
 create mode 100644 fixtures/paragraph-document-language/meta.json
 create mode 100644 fixtures/paragraph-document-language/utterances.json
 create mode 100644 fixtures/paragraph-multilingual-lang-attribute/gnd.json
 create mode 100644 fixtures/paragraph-multilingual-lang-attribute/input.html
 create mode 100644 fixtures/paragraph-multilingual-lang-attribute/meta.json
 create mode 100644 fixtures/paragraph-multilingual-lang-attribute/utterances.json
 create mode 100644 fixtures/paragraph-multilingual-nested/gnd.json
 create mode 100644 fixtures/paragraph-multilingual-nested/input.html
 create mode 100644 fixtures/paragraph-multilingual-nested/meta.json
 create mode 100644 fixtures/paragraph-multilingual-nested/utterances.json
 create mode 100644 fixtures/paragraph-multilingual-repeated-language/gnd.json
 create mode 100644 fixtures/paragraph-multilingual-repeated-language/input.html
 create mode 100644 fixtures/paragraph-multilingual-repeated-language/meta.json
 create mode 100644 fixtures/paragraph-multilingual-repeated-language/utterances.json
 create mode 100644 fixtures/paragraph-multilingual-two-languages/gnd.json
 create mode 100644 fixtures/paragraph-multilingual-two-languages/input.html
 create mode 100644 fixtures/paragraph-multilingual-two-languages/meta.json
 create mode 100644 fixtures/paragraph-multilingual-two-languages/utterances.json
 rename src/gnd/{parseGnd.ts => makeGnd.ts} (58%)
 create mode 100644 src/utterances/announcements.ts
 create mode 100644 src/utterances/extractUtterances.ts
 create mode 100644 src/utterances/index.ts
 create mode 100644 src/utterances/roles.ts
 create mode 100644 src/utterances/text.ts
 create mode 100644 src/utterances/types.ts
 create mode 100644 test/utterances/fixtures.test.ts
 create mode 100644 test/utterances/skip.test.ts

diff --git a/demo/playground/script.js b/demo/playground/script.js
index 1d9c58f..38aa728 100644
--- a/demo/playground/script.js
+++ b/demo/playground/script.js
@@ -9,17 +9,20 @@ const utterancesExpectedEl = document.getElementById("utterances-expected");
 const utterancesActualEl = document.getElementById("utterances-actual");
 const utterancesBadgeEl = document.getElementById("utterances-badge");
 
-// Feature-detect the GND converter, if/when @readium/speech exports one.
-// Utterance extraction (GND -> utterances) isn't implemented yet, so that
-// pane always shows a "not implemented yet" badge regardless.
+// Feature-detect the GND converter and the utterance extractor, if/when
+// @readium/speech exports them.
 let converter = null;
+let utteranceExtractor = null;
 try {
   const mod = await import("../../build/index.js");
   if (typeof mod.convert === "function") {
     converter = mod;
   }
+  if (typeof mod.extractUtterances === "function") {
+    utteranceExtractor = mod;
+  }
 } catch {
-  // build/index.js may not export a converter yet; that's expected pre-implementation.
+  // build/index.js may not export these yet; that's expected pre-implementation.
 }
 
 const manifest = await fetch("../../fixtures/manifest.json").then((r) => r.json());
@@ -188,25 +191,38 @@ async function selectFixture(id) {
   gndExpectedEl.textContent = JSON.stringify(withSchemaKeyOrder(gnd), null, 2);
   utterancesExpectedEl.textContent = JSON.stringify(utterances, null, 2);
 
-  // Utterance extraction is out of scope for now, so that pane never has
-  // anything to run.
-  utterancesActualEl.textContent = "";
-  setBadge(utterancesBadgeEl, "pending");
-
   if (!converter) {
     gndActualEl.textContent = "";
     setBadge(gndBadgeEl, "pending");
+    utterancesActualEl.textContent = "";
+    setBadge(utterancesBadgeEl, "pending");
     return;
   }
 
+  let actual;
   try {
-    const actual = converter.convert(inputHtml);
+    actual = converter.convert(inputHtml);
     gndActualEl.textContent = JSON.stringify(withSchemaKeyOrder(toStoredShape(actual)), null, 2);
     setBadge(gndBadgeEl, deepEqual(actual, expectedTopLevel(gnd)) ? "pass" : "fail");
   } catch (err) {
     gndActualEl.textContent = String(err);
     setBadge(gndBadgeEl, "fail");
   }
+
+  if (!utteranceExtractor || actual === undefined) {
+    utterancesActualEl.textContent = "";
+    setBadge(utterancesBadgeEl, "pending");
+    return;
+  }
+
+  try {
+    const actualUtterances = utteranceExtractor.extractUtterances(actual);
+    utterancesActualEl.textContent = JSON.stringify(actualUtterances, null, 2);
+    setBadge(utterancesBadgeEl, deepEqual(actualUtterances, utterances) ? "pass" : "fail");
+  } catch (err) {
+    utterancesActualEl.textContent = String(err);
+    setBadge(utterancesBadgeEl, "fail");
+  }
 }
 
 filterInput.addEventListener("input", renderList);
diff --git a/fixtures/README.md b/fixtures/README.md
index 2ae831e..14c660e 100644
--- a/fixtures/README.md
+++ b/fixtures/README.md
@@ -29,6 +29,8 @@ fixtures/
     input.html             the HTML input (a fragment or a full document, see meta.json.inputKind)
     gnd.json               the expected Guided Navigation document produced from input.html
     utterances.json        the expected ordered utterance list produced from gnd.json
+    utterances-skipped.json  only present when meta.json.skip is set — the expected
+                             utterance list when skipping the role(s) listed there
 ```
 
 `manifest.json` and `ROLES_COVERAGE.md` are both generated from the
@@ -74,10 +76,30 @@ Each fixture directory is fully self-contained and independently loadable.
   "role": "footnote",                     // the roles.md role name this fixture targets
   "rolesCovered": ["footnote", "noteref"],// every role name this fixture's markup exercises
   "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
-  "inputKind": "document"                 // "fragment" | "document"
+  "inputKind": "document",                // "fragment" | "document"
+  "skip": ["footnote"]                    // optional — see "Skippable roles" below
 }
 ```
 
+## Skippable roles
+
+[roles.md#list-of-skippable-roles](https://github.com/readium/guided-navigation/blob/main/roles.md#list-of-skippable-roles)
+documents roles a *reader* may choose to skip past during playback (asides,
+footnotes, pagebreaks, tables of contents...) — they aren't omitted from
+utterance extraction by default, since every fixture's `utterances.json` is
+the unfiltered baseline. Skipping is instead a filter a consumer opts into
+at extraction time, given a set of roles to omit.
+
+A fixture that exercises a skippable role may set `meta.json`'s optional
+`skip` field to the role(s) to test skipping for, and ship a sibling
+`utterances-skipped.json`: the exact `utterances.json` output, minus every
+node (and its whole subtree) whose role is in `skip`. Consuming this is the
+same as the base utterance check (see below), just with the role filter
+applied and compared against this file instead.
+
+Not every fixture needs this — only ones where skipping is illustrative
+(a footnote reached via noteref, a whole aside, a pagebreak announcement).
+
 ## `epub:type` fixtures are full XHTML documents
 
 `epub:type` is only meaningful in XHTML with the `epub` namespace declared on
@@ -127,15 +149,20 @@ A flat JSON array, one entry per fixture:
     "dir": "footnote-epub-type",
     "role": "footnote",
     "description": "Footnote encoded via epub:type, referenced by a noteref",
+    "skip": ["footnote"],
     "files": {
       "input": "input.html",
       "gnd": "gnd.json",
-      "utterances": "utterances.json"
+      "utterances": "utterances.json",
+      "utterancesSkipped": "utterances-skipped.json"
     }
   }
 ]
 ```
 
+`skip` and `files.utterancesSkipped` are only present on fixtures that ship
+`utterances-skipped.json`.
+
 Any test runner, in any language, reads this one file to discover every
 fixture and resolve its file paths — no directory listing required.
 
@@ -146,7 +173,10 @@ fixture and resolve its file paths — no directory listing required.
    of stage 1 (HTML → GND) — compare the result to `gnd.json`.
 3. Run the resulting GND document through your implementation of stage 2
    (GND → utterances) — compare the result to `utterances.json`.
-4. A fixture "passes" when both comparisons match exactly.
+4. If the entry has a `skip` field, run stage 2 again with that role set
+   passed as your implementation's skip filter — compare the result to
+   `utterances-skipped.json`.
+5. A fixture "passes" when every comparison it has files for matches exactly.
 
 ## Adding a new fixture
 
@@ -154,8 +184,11 @@ fixture and resolve its file paths — no directory listing required.
    markup being tested.
 2. Hand-author `gnd.json` and `utterances.json` — there is no generator for
    these; they are the ground truth implementations must match.
-3. Write `meta.json`.
-4. Run `npm run generate-fixtures-manifest` to regenerate `manifest.json`
+3. If the fixture is illustrative for skipping (see "Skippable roles"
+   above), also hand-author `utterances-skipped.json` and set `meta.json`'s
+   `skip` field.
+4. Write `meta.json`.
+5. Run `npm run generate-fixtures-manifest` to regenerate `manifest.json`
    and `ROLES_COVERAGE.md` from what's now on disk.
 
 ## This suite is not finished
diff --git a/fixtures/ROLES_COVERAGE.md b/fixtures/ROLES_COVERAGE.md
index debe51c..e731593 100644
--- a/fixtures/ROLES_COVERAGE.md
+++ b/fixtures/ROLES_COVERAGE.md
@@ -56,7 +56,7 @@ renaming, or removing a fixture.
 | `notice` | `notice-epub-type`, `notice-role-aria` |
 | `pagebreak` | `pagebreak-epub-type`, `pagebreak-role-aria` |
 | `pagelist` | `pagelist-epub-type`, `pagelist-role-aria` |
-| `paragraph` | `paragraph-basic`, `paragraph-multilingual-ssml-lang` |
+| `paragraph` | `paragraph-basic`, `paragraph-block-level-language`, `paragraph-document-language`, `paragraph-multilingual-lang-attribute`, `paragraph-multilingual-nested`, `paragraph-multilingual-repeated-language`, `paragraph-multilingual-ssml-lang`, `paragraph-multilingual-two-languages` |
 | `part` | `part-epub-type`, `part-role-aria` |
 | `preface` | `preface-epub-type`, `preface-role-aria` |
 | `preformatted` | `preformatted-html-native` |
@@ -75,4 +75,4 @@ renaming, or removing a fixture.
 | `toc` | `toc-epub-type`, `toc-role-aria` |
 | `video` | `video-html-native` |
 
-123 fixtures across 67 roles.
+129 fixtures across 67 roles.
diff --git a/fixtures/abstract-epub-type/utterances.json b/fixtures/abstract-epub-type/utterances.json
index 015e7d5..e98f268 100644
--- a/fixtures/abstract-epub-type/utterances.json
+++ b/fixtures/abstract-epub-type/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "This work examines the maintenance of coastal lighthouses in the 19th century."
+    "plain": "This work examines the maintenance of coastal lighthouses in the 19th century."
   }
 ]
diff --git a/fixtures/abstract-role-aria/utterances.json b/fixtures/abstract-role-aria/utterances.json
index 015e7d5..e98f268 100644
--- a/fixtures/abstract-role-aria/utterances.json
+++ b/fixtures/abstract-role-aria/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "This work examines the maintenance of coastal lighthouses in the 19th century."
+    "plain": "This work examines the maintenance of coastal lighthouses in the 19th century."
   }
 ]
diff --git a/fixtures/acknowledgments-epub-type/utterances.json b/fixtures/acknowledgments-epub-type/utterances.json
index f39975a..ded247f 100644
--- a/fixtures/acknowledgments-epub-type/utterances.json
+++ b/fixtures/acknowledgments-epub-type/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "The author thanks the keepers of Fastnet Rock for their recollections."
+    "plain": "The author thanks the keepers of Fastnet Rock for their recollections."
   }
 ]
diff --git a/fixtures/acknowledgments-role-aria/utterances.json b/fixtures/acknowledgments-role-aria/utterances.json
index f39975a..ded247f 100644
--- a/fixtures/acknowledgments-role-aria/utterances.json
+++ b/fixtures/acknowledgments-role-aria/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "The author thanks the keepers of Fastnet Rock for their recollections."
+    "plain": "The author thanks the keepers of Fastnet Rock for their recollections."
   }
 ]
diff --git a/fixtures/afterword-epub-type/utterances.json b/fixtures/afterword-epub-type/utterances.json
index 26e238c..fc9f423 100644
--- a/fixtures/afterword-epub-type/utterances.json
+++ b/fixtures/afterword-epub-type/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "Years later, the last lighthouse keeper reflects on automation."
+    "plain": "Years later, the last lighthouse keeper reflects on automation."
   }
 ]
diff --git a/fixtures/afterword-role-aria/utterances.json b/fixtures/afterword-role-aria/utterances.json
index 26e238c..fc9f423 100644
--- a/fixtures/afterword-role-aria/utterances.json
+++ b/fixtures/afterword-role-aria/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "Years later, the last lighthouse keeper reflects on automation."
+    "plain": "Years later, the last lighthouse keeper reflects on automation."
   }
 ]
diff --git a/fixtures/appendix-epub-type/utterances.json b/fixtures/appendix-epub-type/utterances.json
index dddcc84..514edbc 100644
--- a/fixtures/appendix-epub-type/utterances.json
+++ b/fixtures/appendix-epub-type/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "A table of lighthouse construction dates referenced in the text."
+    "plain": "A table of lighthouse construction dates referenced in the text."
   }
 ]
diff --git a/fixtures/appendix-role-aria/utterances.json b/fixtures/appendix-role-aria/utterances.json
index dddcc84..514edbc 100644
--- a/fixtures/appendix-role-aria/utterances.json
+++ b/fixtures/appendix-role-aria/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "A table of lighthouse construction dates referenced in the text."
+    "plain": "A table of lighthouse construction dates referenced in the text."
   }
 ]
diff --git a/fixtures/article-html-native/utterances.json b/fixtures/article-html-native/utterances.json
index 24789d1..ad408d7 100644
--- a/fixtures/article-html-native/utterances.json
+++ b/fixtures/article-html-native/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "A self-contained article about lighthouse keeping."
+    "plain": "A self-contained article about lighthouse keeping."
   }
 ]
diff --git a/fixtures/aside-html-native/meta.json b/fixtures/aside-html-native/meta.json
index 87272cc..117ff92 100644
--- a/fixtures/aside-html-native/meta.json
+++ b/fixtures/aside-html-native/meta.json
@@ -6,5 +6,6 @@
     "aside"
   ],
   "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
-  "inputKind": "fragment"
+  "inputKind": "fragment",
+  "skip": ["aside"]
 }
diff --git a/fixtures/aside-html-native/utterances-skipped.json b/fixtures/aside-html-native/utterances-skipped.json
new file mode 100644
index 0000000..fe51488
--- /dev/null
+++ b/fixtures/aside-html-native/utterances-skipped.json
@@ -0,0 +1 @@
+[]
diff --git a/fixtures/aside-html-native/utterances.json b/fixtures/aside-html-native/utterances.json
index 37454b2..2daf50b 100644
--- a/fixtures/aside-html-native/utterances.json
+++ b/fixtures/aside-html-native/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "By the way, lighthouses were once staffed around the clock."
+    "plain": "By the way, lighthouses were once staffed around the clock."
   }
 ]
diff --git a/fixtures/audio-html-native/utterances.json b/fixtures/audio-html-native/utterances.json
index 43698a2..4b371cf 100644
--- a/fixtures/audio-html-native/utterances.json
+++ b/fixtures/audio-html-native/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "Foghorn recording from the 1962 restoration"
+    "plain": "Foghorn recording from the 1962 restoration"
   }
 ]
diff --git a/fixtures/backlink-epub-type/utterances.json b/fixtures/backlink-epub-type/utterances.json
index a422901..f32b425 100644
--- a/fixtures/backlink-epub-type/utterances.json
+++ b/fixtures/backlink-epub-type/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "Return to reference"
+    "plain": "Return to reference"
   }
 ]
diff --git a/fixtures/backlink-role-aria/utterances.json b/fixtures/backlink-role-aria/utterances.json
index a422901..f32b425 100644
--- a/fixtures/backlink-role-aria/utterances.json
+++ b/fixtures/backlink-role-aria/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "Return to reference"
+    "plain": "Return to reference"
   }
 ]
diff --git a/fixtures/bibliography-epub-type/utterances.json b/fixtures/bibliography-epub-type/utterances.json
index c3778b6..c1bf5a3 100644
--- a/fixtures/bibliography-epub-type/utterances.json
+++ b/fixtures/bibliography-epub-type/utterances.json
@@ -1,8 +1,8 @@
 [
   {
-    "text": "Smith, J. Lighthouses of the Atlantic. 1988."
+    "plain": "Smith, J. Lighthouses of the Atlantic. 1988."
   },
   {
-    "text": "Doe, A. Coastal Illumination. 1975."
+    "plain": "Doe, A. Coastal Illumination. 1975."
   }
 ]
diff --git a/fixtures/bibliography-role-aria/utterances.json b/fixtures/bibliography-role-aria/utterances.json
index c3778b6..c1bf5a3 100644
--- a/fixtures/bibliography-role-aria/utterances.json
+++ b/fixtures/bibliography-role-aria/utterances.json
@@ -1,8 +1,8 @@
 [
   {
-    "text": "Smith, J. Lighthouses of the Atlantic. 1988."
+    "plain": "Smith, J. Lighthouses of the Atlantic. 1988."
   },
   {
-    "text": "Doe, A. Coastal Illumination. 1975."
+    "plain": "Doe, A. Coastal Illumination. 1975."
   }
 ]
diff --git a/fixtures/biblioref-epub-type/utterances.json b/fixtures/biblioref-epub-type/utterances.json
index 534be16..8740d24 100644
--- a/fixtures/biblioref-epub-type/utterances.json
+++ b/fixtures/biblioref-epub-type/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "See Smith, 1988"
+    "plain": "See Smith, 1988"
   }
 ]
diff --git a/fixtures/biblioref-role-aria/utterances.json b/fixtures/biblioref-role-aria/utterances.json
index 534be16..8740d24 100644
--- a/fixtures/biblioref-role-aria/utterances.json
+++ b/fixtures/biblioref-role-aria/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "See Smith, 1988"
+    "plain": "See Smith, 1988"
   }
 ]
diff --git a/fixtures/blockquote-html-native/utterances.json b/fixtures/blockquote-html-native/utterances.json
index ac4c2e2..98227d2 100644
--- a/fixtures/blockquote-html-native/utterances.json
+++ b/fixtures/blockquote-html-native/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "To be, or not to be, that is the question."
+    "plain": "To be, or not to be, that is the question."
   }
 ]
diff --git a/fixtures/body-html-native/utterances.json b/fixtures/body-html-native/utterances.json
index 570855c..6138e6f 100644
--- a/fixtures/body-html-native/utterances.json
+++ b/fixtures/body-html-native/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "The full content of the document."
+    "plain": "The full content of the document."
   }
 ]
diff --git a/fixtures/chapter-epub-type/utterances.json b/fixtures/chapter-epub-type/utterances.json
index 3f67223..55f8470 100644
--- a/fixtures/chapter-epub-type/utterances.json
+++ b/fixtures/chapter-epub-type/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "Title of the chapter"
+    "plain": "Title of the chapter"
   }
 ]
diff --git a/fixtures/chapter-role-aria/utterances.json b/fixtures/chapter-role-aria/utterances.json
index 3f67223..55f8470 100644
--- a/fixtures/chapter-role-aria/utterances.json
+++ b/fixtures/chapter-role-aria/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "Title of the chapter"
+    "plain": "Title of the chapter"
   }
 ]
diff --git a/fixtures/colophon-epub-type/utterances.json b/fixtures/colophon-epub-type/utterances.json
index 1123dab..0232ee1 100644
--- a/fixtures/colophon-epub-type/utterances.json
+++ b/fixtures/colophon-epub-type/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "Set in Georgia, 11pt, on recycled paper."
+    "plain": "Set in Georgia, 11pt, on recycled paper."
   }
 ]
diff --git a/fixtures/colophon-role-aria/utterances.json b/fixtures/colophon-role-aria/utterances.json
index 1123dab..0232ee1 100644
--- a/fixtures/colophon-role-aria/utterances.json
+++ b/fixtures/colophon-role-aria/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "Set in Georgia, 11pt, on recycled paper."
+    "plain": "Set in Georgia, 11pt, on recycled paper."
   }
 ]
diff --git a/fixtures/complementary-role-aria/utterances.json b/fixtures/complementary-role-aria/utterances.json
index 662441f..66e157d 100644
--- a/fixtures/complementary-role-aria/utterances.json
+++ b/fixtures/complementary-role-aria/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "A supporting note related to the main content."
+    "plain": "A supporting note related to the main content."
   }
 ]
diff --git a/fixtures/conclusion-epub-type/utterances.json b/fixtures/conclusion-epub-type/utterances.json
index 209d60e..da383c0 100644
--- a/fixtures/conclusion-epub-type/utterances.json
+++ b/fixtures/conclusion-epub-type/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "Lighthouses remain a symbol of safe passage."
+    "plain": "Lighthouses remain a symbol of safe passage."
   }
 ]
diff --git a/fixtures/conclusion-role-aria/utterances.json b/fixtures/conclusion-role-aria/utterances.json
index 209d60e..da383c0 100644
--- a/fixtures/conclusion-role-aria/utterances.json
+++ b/fixtures/conclusion-role-aria/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "Lighthouses remain a symbol of safe passage."
+    "plain": "Lighthouses remain a symbol of safe passage."
   }
 ]
diff --git a/fixtures/cover-epub-type/utterances.json b/fixtures/cover-epub-type/utterances.json
index 9a0ddb4..01408d7 100644
--- a/fixtures/cover-epub-type/utterances.json
+++ b/fixtures/cover-epub-type/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "Lighthouses of the Atlantic, by J. Smith"
+    "plain": "Lighthouses of the Atlantic, by J. Smith"
   }
 ]
diff --git a/fixtures/cover-role-aria/utterances.json b/fixtures/cover-role-aria/utterances.json
index 9a0ddb4..01408d7 100644
--- a/fixtures/cover-role-aria/utterances.json
+++ b/fixtures/cover-role-aria/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "Lighthouses of the Atlantic, by J. Smith"
+    "plain": "Lighthouses of the Atlantic, by J. Smith"
   }
 ]
diff --git a/fixtures/credit-epub-type/utterances.json b/fixtures/credit-epub-type/utterances.json
index f4f21e0..ea556e4 100644
--- a/fixtures/credit-epub-type/utterances.json
+++ b/fixtures/credit-epub-type/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "Cover photograph by A. Keeper."
+    "plain": "Cover photograph by A. Keeper."
   }
 ]
diff --git a/fixtures/credit-role-aria/utterances.json b/fixtures/credit-role-aria/utterances.json
index f4f21e0..ea556e4 100644
--- a/fixtures/credit-role-aria/utterances.json
+++ b/fixtures/credit-role-aria/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "Cover photograph by A. Keeper."
+    "plain": "Cover photograph by A. Keeper."
   }
 ]
diff --git a/fixtures/credits-epub-type/utterances.json b/fixtures/credits-epub-type/utterances.json
index efc3de9..987e8cb 100644
--- a/fixtures/credits-epub-type/utterances.json
+++ b/fixtures/credits-epub-type/utterances.json
@@ -1,8 +1,8 @@
 [
   {
-    "text": "Cover photograph by A. Keeper."
+    "plain": "Cover photograph by A. Keeper."
   },
   {
-    "text": "Maps by B. Cartographer."
+    "plain": "Maps by B. Cartographer."
   }
 ]
diff --git a/fixtures/credits-role-aria/utterances.json b/fixtures/credits-role-aria/utterances.json
index efc3de9..987e8cb 100644
--- a/fixtures/credits-role-aria/utterances.json
+++ b/fixtures/credits-role-aria/utterances.json
@@ -1,8 +1,8 @@
 [
   {
-    "text": "Cover photograph by A. Keeper."
+    "plain": "Cover photograph by A. Keeper."
   },
   {
-    "text": "Maps by B. Cartographer."
+    "plain": "Maps by B. Cartographer."
   }
 ]
diff --git a/fixtures/dedication-epub-type/utterances.json b/fixtures/dedication-epub-type/utterances.json
index 6a7ce00..12e1744 100644
--- a/fixtures/dedication-epub-type/utterances.json
+++ b/fixtures/dedication-epub-type/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "For every keeper who lit the lamp at dusk."
+    "plain": "For every keeper who lit the lamp at dusk."
   }
 ]
diff --git a/fixtures/dedication-role-aria/utterances.json b/fixtures/dedication-role-aria/utterances.json
index 6a7ce00..12e1744 100644
--- a/fixtures/dedication-role-aria/utterances.json
+++ b/fixtures/dedication-role-aria/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "For every keeper who lit the lamp at dusk."
+    "plain": "For every keeper who lit the lamp at dusk."
   }
 ]
diff --git a/fixtures/definition-epub-type/utterances.json b/fixtures/definition-epub-type/utterances.json
index 1919e54..269bed0 100644
--- a/fixtures/definition-epub-type/utterances.json
+++ b/fixtures/definition-epub-type/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "A structure that contains an enumeration of related content items."
+    "plain": "A structure that contains an enumeration of related content items."
   }
 ]
diff --git a/fixtures/definition-html-native/utterances.json b/fixtures/definition-html-native/utterances.json
index 1919e54..269bed0 100644
--- a/fixtures/definition-html-native/utterances.json
+++ b/fixtures/definition-html-native/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "A structure that contains an enumeration of related content items."
+    "plain": "A structure that contains an enumeration of related content items."
   }
 ]
diff --git a/fixtures/definition-role-aria/utterances.json b/fixtures/definition-role-aria/utterances.json
index 1919e54..269bed0 100644
--- a/fixtures/definition-role-aria/utterances.json
+++ b/fixtures/definition-role-aria/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "A structure that contains an enumeration of related content items."
+    "plain": "A structure that contains an enumeration of related content items."
   }
 ]
diff --git a/fixtures/details-html-native/utterances.json b/fixtures/details-html-native/utterances.json
index 7afa710..f02d095 100644
--- a/fixtures/details-html-native/utterances.json
+++ b/fixtures/details-html-native/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "Additional details the reader can expand."
+    "plain": "Additional details the reader can expand."
   }
 ]
diff --git a/fixtures/endnotes-epub-type/utterances.json b/fixtures/endnotes-epub-type/utterances.json
index 8ad996d..24e0548 100644
--- a/fixtures/endnotes-epub-type/utterances.json
+++ b/fixtures/endnotes-epub-type/utterances.json
@@ -1,8 +1,8 @@
 [
   {
-    "text": "See introduction for background."
+    "plain": "See introduction for background."
   },
   {
-    "text": "See chapter three for details."
+    "plain": "See chapter three for details."
   }
 ]
diff --git a/fixtures/endnotes-role-aria/utterances.json b/fixtures/endnotes-role-aria/utterances.json
index 8ad996d..24e0548 100644
--- a/fixtures/endnotes-role-aria/utterances.json
+++ b/fixtures/endnotes-role-aria/utterances.json
@@ -1,8 +1,8 @@
 [
   {
-    "text": "See introduction for background."
+    "plain": "See introduction for background."
   },
   {
-    "text": "See chapter three for details."
+    "plain": "See chapter three for details."
   }
 ]
diff --git a/fixtures/epigraph-epub-type/utterances.json b/fixtures/epigraph-epub-type/utterances.json
index e49b485..e5c70d9 100644
--- a/fixtures/epigraph-epub-type/utterances.json
+++ b/fixtures/epigraph-epub-type/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "A lighthouse is a compromise with the sea. — Anonymous"
+    "plain": "A lighthouse is a compromise with the sea. — Anonymous"
   }
 ]
diff --git a/fixtures/epigraph-role-aria/utterances.json b/fixtures/epigraph-role-aria/utterances.json
index e49b485..e5c70d9 100644
--- a/fixtures/epigraph-role-aria/utterances.json
+++ b/fixtures/epigraph-role-aria/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "A lighthouse is a compromise with the sea. — Anonymous"
+    "plain": "A lighthouse is a compromise with the sea. — Anonymous"
   }
 ]
diff --git a/fixtures/epilogue-epub-type/utterances.json b/fixtures/epilogue-epub-type/utterances.json
index bbbf7ab..d2d00eb 100644
--- a/fixtures/epilogue-epub-type/utterances.json
+++ b/fixtures/epilogue-epub-type/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "The lamp still turns, though no one climbs the stairs anymore."
+    "plain": "The lamp still turns, though no one climbs the stairs anymore."
   }
 ]
diff --git a/fixtures/epilogue-role-aria/utterances.json b/fixtures/epilogue-role-aria/utterances.json
index bbbf7ab..d2d00eb 100644
--- a/fixtures/epilogue-role-aria/utterances.json
+++ b/fixtures/epilogue-role-aria/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "The lamp still turns, though no one climbs the stairs anymore."
+    "plain": "The lamp still turns, though no one climbs the stairs anymore."
   }
 ]
diff --git a/fixtures/errata-epub-type/utterances.json b/fixtures/errata-epub-type/utterances.json
index c8f7308..aa063c3 100644
--- a/fixtures/errata-epub-type/utterances.json
+++ b/fixtures/errata-epub-type/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "Page 42: 'lightouse' should read 'lighthouse'."
+    "plain": "Page 42: 'lightouse' should read 'lighthouse'."
   }
 ]
diff --git a/fixtures/errata-role-aria/utterances.json b/fixtures/errata-role-aria/utterances.json
index c8f7308..aa063c3 100644
--- a/fixtures/errata-role-aria/utterances.json
+++ b/fixtures/errata-role-aria/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "Page 42: 'lightouse' should read 'lighthouse'."
+    "plain": "Page 42: 'lightouse' should read 'lighthouse'."
   }
 ]
diff --git a/fixtures/example-epub-type/utterances.json b/fixtures/example-epub-type/utterances.json
index 56e0d23..d4f1fa6 100644
--- a/fixtures/example-epub-type/utterances.json
+++ b/fixtures/example-epub-type/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "For instance, a Fresnel lens focuses light into a narrow beam."
+    "plain": "For instance, a Fresnel lens focuses light into a narrow beam."
   }
 ]
diff --git a/fixtures/example-role-aria/utterances.json b/fixtures/example-role-aria/utterances.json
index 56e0d23..d4f1fa6 100644
--- a/fixtures/example-role-aria/utterances.json
+++ b/fixtures/example-role-aria/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "For instance, a Fresnel lens focuses light into a narrow beam."
+    "plain": "For instance, a Fresnel lens focuses light into a narrow beam."
   }
 ]
diff --git a/fixtures/figure-basic-epub-type/utterances.json b/fixtures/figure-basic-epub-type/utterances.json
index 2ce891d..4265c35 100644
--- a/fixtures/figure-basic-epub-type/utterances.json
+++ b/fixtures/figure-basic-epub-type/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "A bar chart showing sales growth"
+    "plain": "A bar chart showing sales growth"
   }
 ]
diff --git a/fixtures/figure-basic-html-native/utterances.json b/fixtures/figure-basic-html-native/utterances.json
index 2ce891d..4265c35 100644
--- a/fixtures/figure-basic-html-native/utterances.json
+++ b/fixtures/figure-basic-html-native/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "A bar chart showing sales growth"
+    "plain": "A bar chart showing sales growth"
   }
 ]
diff --git a/fixtures/figure-basic-role-aria/utterances.json b/fixtures/figure-basic-role-aria/utterances.json
index 2ce891d..4265c35 100644
--- a/fixtures/figure-basic-role-aria/utterances.json
+++ b/fixtures/figure-basic-role-aria/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "A bar chart showing sales growth"
+    "plain": "A bar chart showing sales growth"
   }
 ]
diff --git a/fixtures/figure-caption-html-native/utterances.json b/fixtures/figure-caption-html-native/utterances.json
index c0e12c1..ce3a3d2 100644
--- a/fixtures/figure-caption-html-native/utterances.json
+++ b/fixtures/figure-caption-html-native/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "ASCII Art of a cat face"
+    "plain": "ASCII Art of a cat face"
   }
 ]
diff --git a/fixtures/figure-caption-role-aria/utterances.json b/fixtures/figure-caption-role-aria/utterances.json
index c0e12c1..ce3a3d2 100644
--- a/fixtures/figure-caption-role-aria/utterances.json
+++ b/fixtures/figure-caption-role-aria/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "ASCII Art of a cat face"
+    "plain": "ASCII Art of a cat face"
   }
 ]
diff --git a/fixtures/figure-describedby/utterances.json b/fixtures/figure-describedby/utterances.json
index 7f773ed..8336cd9 100644
--- a/fixtures/figure-describedby/utterances.json
+++ b/fixtures/figure-describedby/utterances.json
@@ -1,5 +1,8 @@
 [
   {
-    "text": "Full audio description: sales grew 12% year over year, driven primarily by the Q4 holiday season."
+    "plain": "Sales chart"
+  },
+  {
+    "plain": "Full audio description: sales grew 12% year over year, driven primarily by the Q4 holiday season."
   }
 ]
diff --git a/fixtures/footnote-epub-type/meta.json b/fixtures/footnote-epub-type/meta.json
index 3731633..1748196 100644
--- a/fixtures/footnote-epub-type/meta.json
+++ b/fixtures/footnote-epub-type/meta.json
@@ -7,5 +7,6 @@
     "noteref"
   ],
   "sourceRef": "https://github.com/readium/guided-navigation/tree/main/examples/read-aloud",
-  "inputKind": "document"
+  "inputKind": "document",
+  "skip": ["footnote"]
 }
diff --git a/fixtures/footnote-epub-type/utterances-skipped.json b/fixtures/footnote-epub-type/utterances-skipped.json
new file mode 100644
index 0000000..70c490e
--- /dev/null
+++ b/fixtures/footnote-epub-type/utterances-skipped.json
@@ -0,0 +1,6 @@
+[
+  {
+    "plain": "This text has a footnote.",
+    "language": "en"
+  }
+]
diff --git a/fixtures/footnote-epub-type/utterances.json b/fixtures/footnote-epub-type/utterances.json
index 47eecb0..b9d07c3 100644
--- a/fixtures/footnote-epub-type/utterances.json
+++ b/fixtures/footnote-epub-type/utterances.json
@@ -1,8 +1,15 @@
 [
   {
-    "text": "This text has a footnote."
+    "plain": "This text has a footnote.",
+    "language": "en"
   },
   {
-    "text": "Start of the footnote. Text of the footnote. End of the footnote."
+    "plain": "Start of the footnote."
+  },
+  {
+    "plain": "Text of the footnote."
+  },
+  {
+    "plain": "End of the footnote."
   }
 ]
diff --git a/fixtures/footnote-role-aria/meta.json b/fixtures/footnote-role-aria/meta.json
index 8175572..3fa217c 100644
--- a/fixtures/footnote-role-aria/meta.json
+++ b/fixtures/footnote-role-aria/meta.json
@@ -7,5 +7,6 @@
     "noteref"
   ],
   "sourceRef": "https://github.com/readium/guided-navigation/tree/main/examples/read-aloud",
-  "inputKind": "fragment"
+  "inputKind": "fragment",
+  "skip": ["footnote"]
 }
diff --git a/fixtures/footnote-role-aria/utterances-skipped.json b/fixtures/footnote-role-aria/utterances-skipped.json
new file mode 100644
index 0000000..70c490e
--- /dev/null
+++ b/fixtures/footnote-role-aria/utterances-skipped.json
@@ -0,0 +1,6 @@
+[
+  {
+    "plain": "This text has a footnote.",
+    "language": "en"
+  }
+]
diff --git a/fixtures/footnote-role-aria/utterances.json b/fixtures/footnote-role-aria/utterances.json
index 47eecb0..b9d07c3 100644
--- a/fixtures/footnote-role-aria/utterances.json
+++ b/fixtures/footnote-role-aria/utterances.json
@@ -1,8 +1,15 @@
 [
   {
-    "text": "This text has a footnote."
+    "plain": "This text has a footnote.",
+    "language": "en"
   },
   {
-    "text": "Start of the footnote. Text of the footnote. End of the footnote."
+    "plain": "Start of the footnote."
+  },
+  {
+    "plain": "Text of the footnote."
+  },
+  {
+    "plain": "End of the footnote."
   }
 ]
diff --git a/fixtures/foreword-epub-type/utterances.json b/fixtures/foreword-epub-type/utterances.json
index 16ad612..9dd5982 100644
--- a/fixtures/foreword-epub-type/utterances.json
+++ b/fixtures/foreword-epub-type/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "A respected maritime historian introduces this account of the coastline's lighthouses."
+    "plain": "A respected maritime historian introduces this account of the coastline's lighthouses."
   }
 ]
diff --git a/fixtures/foreword-role-aria/utterances.json b/fixtures/foreword-role-aria/utterances.json
index 16ad612..9dd5982 100644
--- a/fixtures/foreword-role-aria/utterances.json
+++ b/fixtures/foreword-role-aria/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "A respected maritime historian introduces this account of the coastline's lighthouses."
+    "plain": "A respected maritime historian introduces this account of the coastline's lighthouses."
   }
 ]
diff --git a/fixtures/glossary-epub-type/utterances.json b/fixtures/glossary-epub-type/utterances.json
index 2d2d7c7..cdc7709 100644
--- a/fixtures/glossary-epub-type/utterances.json
+++ b/fixtures/glossary-epub-type/utterances.json
@@ -1,14 +1,14 @@
 [
   {
-    "text": "Fresnel lens"
+    "plain": "Fresnel lens"
   },
   {
-    "text": "A compact lens for focusing light."
+    "plain": "A compact lens for focusing light."
   },
   {
-    "text": "Keeper"
+    "plain": "Keeper"
   },
   {
-    "text": "A person responsible for maintaining a lighthouse."
+    "plain": "A person responsible for maintaining a lighthouse."
   }
 ]
diff --git a/fixtures/glossary-role-aria/utterances.json b/fixtures/glossary-role-aria/utterances.json
index 2d2d7c7..cdc7709 100644
--- a/fixtures/glossary-role-aria/utterances.json
+++ b/fixtures/glossary-role-aria/utterances.json
@@ -1,14 +1,14 @@
 [
   {
-    "text": "Fresnel lens"
+    "plain": "Fresnel lens"
   },
   {
-    "text": "A compact lens for focusing light."
+    "plain": "A compact lens for focusing light."
   },
   {
-    "text": "Keeper"
+    "plain": "Keeper"
   },
   {
-    "text": "A person responsible for maintaining a lighthouse."
+    "plain": "A person responsible for maintaining a lighthouse."
   }
 ]
diff --git a/fixtures/glossref-epub-type/utterances.json b/fixtures/glossref-epub-type/utterances.json
index bbf831f..d210f59 100644
--- a/fixtures/glossref-epub-type/utterances.json
+++ b/fixtures/glossref-epub-type/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "See glossary: Fresnel lens"
+    "plain": "See glossary: Fresnel lens"
   }
 ]
diff --git a/fixtures/glossref-role-aria/utterances.json b/fixtures/glossref-role-aria/utterances.json
index bbf831f..d210f59 100644
--- a/fixtures/glossref-role-aria/utterances.json
+++ b/fixtures/glossref-role-aria/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "See glossary: Fresnel lens"
+    "plain": "See glossary: Fresnel lens"
   }
 ]
diff --git a/fixtures/header-html-native/utterances.json b/fixtures/header-html-native/utterances.json
index 55b5c82..6f02f7e 100644
--- a/fixtures/header-html-native/utterances.json
+++ b/fixtures/header-html-native/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "Chapter One"
+    "plain": "Chapter One"
   }
 ]
diff --git a/fixtures/heading-html-native/utterances.json b/fixtures/heading-html-native/utterances.json
index 65d9331..f3fede9 100644
--- a/fixtures/heading-html-native/utterances.json
+++ b/fixtures/heading-html-native/utterances.json
@@ -1,20 +1,20 @@
 [
   {
-    "text": "Chapter One"
+    "plain": "Chapter One"
   },
   {
-    "text": "Section A"
+    "plain": "Section A"
   },
   {
-    "text": "Subsection i"
+    "plain": "Subsection i"
   },
   {
-    "text": "Detail heading"
+    "plain": "Detail heading"
   },
   {
-    "text": "Note heading"
+    "plain": "Note heading"
   },
   {
-    "text": "Aside heading"
+    "plain": "Aside heading"
   }
 ]
diff --git a/fixtures/heading-role-aria/utterances.json b/fixtures/heading-role-aria/utterances.json
index 65d9331..f3fede9 100644
--- a/fixtures/heading-role-aria/utterances.json
+++ b/fixtures/heading-role-aria/utterances.json
@@ -1,20 +1,20 @@
 [
   {
-    "text": "Chapter One"
+    "plain": "Chapter One"
   },
   {
-    "text": "Section A"
+    "plain": "Section A"
   },
   {
-    "text": "Subsection i"
+    "plain": "Subsection i"
   },
   {
-    "text": "Detail heading"
+    "plain": "Detail heading"
   },
   {
-    "text": "Note heading"
+    "plain": "Note heading"
   },
   {
-    "text": "Aside heading"
+    "plain": "Aside heading"
   }
 ]
diff --git a/fixtures/image-alt-html-native/utterances.json b/fixtures/image-alt-html-native/utterances.json
index bfc6fcf..735235b 100644
--- a/fixtures/image-alt-html-native/utterances.json
+++ b/fixtures/image-alt-html-native/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "Alternative text using the alt attribute"
+    "plain": "Alternative text using the alt attribute"
   }
 ]
diff --git a/fixtures/image-decorative-empty-alt/utterances.json b/fixtures/image-decorative-empty-alt/utterances.json
index 6c54da0..e8e200a 100644
--- a/fixtures/image-decorative-empty-alt/utterances.json
+++ b/fixtures/image-decorative-empty-alt/utterances.json
@@ -1,8 +1,8 @@
 [
   {
-    "text": "Before the divider."
+    "plain": "Before the divider."
   },
   {
-    "text": "After the divider."
+    "plain": "After the divider."
   }
 ]
diff --git a/fixtures/image-decorative-role-presentation/utterances.json b/fixtures/image-decorative-role-presentation/utterances.json
index 6c54da0..e8e200a 100644
--- a/fixtures/image-decorative-role-presentation/utterances.json
+++ b/fixtures/image-decorative-role-presentation/utterances.json
@@ -1,8 +1,8 @@
 [
   {
-    "text": "Before the divider."
+    "plain": "Before the divider."
   },
   {
-    "text": "After the divider."
+    "plain": "After the divider."
   }
 ]
diff --git a/fixtures/image-role-aria/utterances.json b/fixtures/image-role-aria/utterances.json
index 8c04a58..52c07ef 100644
--- a/fixtures/image-role-aria/utterances.json
+++ b/fixtures/image-role-aria/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "Rating: 4 out of 5 stars"
+    "plain": "Rating: 4 out of 5 stars"
   }
 ]
diff --git a/fixtures/index-epub-type/utterances.json b/fixtures/index-epub-type/utterances.json
index 85bb81d..2c2b474 100644
--- a/fixtures/index-epub-type/utterances.json
+++ b/fixtures/index-epub-type/utterances.json
@@ -1,8 +1,8 @@
 [
   {
-    "text": "Fresnel lens"
+    "plain": "Fresnel lens"
   },
   {
-    "text": "Keepers"
+    "plain": "Keepers"
   }
 ]
diff --git a/fixtures/index-role-aria/utterances.json b/fixtures/index-role-aria/utterances.json
index 85bb81d..2c2b474 100644
--- a/fixtures/index-role-aria/utterances.json
+++ b/fixtures/index-role-aria/utterances.json
@@ -1,8 +1,8 @@
 [
   {
-    "text": "Fresnel lens"
+    "plain": "Fresnel lens"
   },
   {
-    "text": "Keepers"
+    "plain": "Keepers"
   }
 ]
diff --git a/fixtures/introduction-epub-type/utterances.json b/fixtures/introduction-epub-type/utterances.json
index a4f0a1b..9e83f9d 100644
--- a/fixtures/introduction-epub-type/utterances.json
+++ b/fixtures/introduction-epub-type/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "This work explores the history of coastal lighthouses."
+    "plain": "This work explores the history of coastal lighthouses."
   }
 ]
diff --git a/fixtures/introduction-role-aria/utterances.json b/fixtures/introduction-role-aria/utterances.json
index a4f0a1b..9e83f9d 100644
--- a/fixtures/introduction-role-aria/utterances.json
+++ b/fixtures/introduction-role-aria/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "This work explores the history of coastal lighthouses."
+    "plain": "This work explores the history of coastal lighthouses."
   }
 ]
diff --git a/fixtures/landmarks-epub-type/utterances.json b/fixtures/landmarks-epub-type/utterances.json
index 3d06b6c..cf62d19 100644
--- a/fixtures/landmarks-epub-type/utterances.json
+++ b/fixtures/landmarks-epub-type/utterances.json
@@ -1,11 +1,11 @@
 [
   {
-    "text": "Cover"
+    "plain": "Cover"
   },
   {
-    "text": "Table of Contents"
+    "plain": "Table of Contents"
   },
   {
-    "text": "Start of Content"
+    "plain": "Start of Content"
   }
 ]
diff --git a/fixtures/list-html-native/utterances.json b/fixtures/list-html-native/utterances.json
index 8e8c458..5e68b82 100644
--- a/fixtures/list-html-native/utterances.json
+++ b/fixtures/list-html-native/utterances.json
@@ -1,11 +1,11 @@
 [
   {
-    "text": "First item"
+    "plain": "First item"
   },
   {
-    "text": "Second item"
+    "plain": "Second item"
   },
   {
-    "text": "Third item"
+    "plain": "Third item"
   }
 ]
diff --git a/fixtures/list-role-aria/utterances.json b/fixtures/list-role-aria/utterances.json
index 8e8c458..5e68b82 100644
--- a/fixtures/list-role-aria/utterances.json
+++ b/fixtures/list-role-aria/utterances.json
@@ -1,11 +1,11 @@
 [
   {
-    "text": "First item"
+    "plain": "First item"
   },
   {
-    "text": "Second item"
+    "plain": "Second item"
   },
   {
-    "text": "Third item"
+    "plain": "Third item"
   }
 ]
diff --git a/fixtures/loa-epub-type/utterances.json b/fixtures/loa-epub-type/utterances.json
index c790d26..67732e5 100644
--- a/fixtures/loa-epub-type/utterances.json
+++ b/fixtures/loa-epub-type/utterances.json
@@ -1,8 +1,8 @@
 [
   {
-    "text": "Audio 1. Foghorn recording"
+    "plain": "Audio 1. Foghorn recording"
   },
   {
-    "text": "Audio 2. Keeper's log reading"
+    "plain": "Audio 2. Keeper's log reading"
   }
 ]
diff --git a/fixtures/loi-epub-type/utterances.json b/fixtures/loi-epub-type/utterances.json
index fe0ea2d..ab995b1 100644
--- a/fixtures/loi-epub-type/utterances.json
+++ b/fixtures/loi-epub-type/utterances.json
@@ -1,8 +1,8 @@
 [
   {
-    "text": "Figure 1. Lighthouse cross-section"
+    "plain": "Figure 1. Lighthouse cross-section"
   },
   {
-    "text": "Figure 2. Fresnel lens diagram"
+    "plain": "Figure 2. Fresnel lens diagram"
   }
 ]
diff --git a/fixtures/lot-epub-type/utterances.json b/fixtures/lot-epub-type/utterances.json
index 9881e95..8b8a724 100644
--- a/fixtures/lot-epub-type/utterances.json
+++ b/fixtures/lot-epub-type/utterances.json
@@ -1,8 +1,8 @@
 [
   {
-    "text": "Table 1. Lighthouse construction dates"
+    "plain": "Table 1. Lighthouse construction dates"
   },
   {
-    "text": "Table 2. Keeper staffing by decade"
+    "plain": "Table 2. Keeper staffing by decade"
   }
 ]
diff --git a/fixtures/lov-epub-type/utterances.json b/fixtures/lov-epub-type/utterances.json
index be20c2b..a4f9cb2 100644
--- a/fixtures/lov-epub-type/utterances.json
+++ b/fixtures/lov-epub-type/utterances.json
@@ -1,8 +1,8 @@
 [
   {
-    "text": "Video 1. Lamp mechanism in motion"
+    "plain": "Video 1. Lamp mechanism in motion"
   },
   {
-    "text": "Video 2. Automation retrofit"
+    "plain": "Video 2. Automation retrofit"
   }
 ]
diff --git a/fixtures/main-html-native/utterances.json b/fixtures/main-html-native/utterances.json
index 19cc243..432fd08 100644
--- a/fixtures/main-html-native/utterances.json
+++ b/fixtures/main-html-native/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "The central topic of this document."
+    "plain": "The central topic of this document."
   }
 ]
diff --git a/fixtures/main-role-aria/utterances.json b/fixtures/main-role-aria/utterances.json
index 19cc243..432fd08 100644
--- a/fixtures/main-role-aria/utterances.json
+++ b/fixtures/main-role-aria/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "The central topic of this document."
+    "plain": "The central topic of this document."
   }
 ]
diff --git a/fixtures/manifest.json b/fixtures/manifest.json
index 11518fb..c279861 100644
--- a/fixtures/manifest.json
+++ b/fixtures/manifest.json
@@ -106,8 +106,12 @@
     "files": {
       "input": "input.html",
       "gnd": "gnd.json",
-      "utterances": "utterances.json"
-    }
+      "utterances": "utterances.json",
+      "utterancesSkipped": "utterances-skipped.json"
+    },
+    "skip": [
+      "aside"
+    ]
   },
   {
     "id": "audio-html-native",
@@ -601,8 +605,12 @@
     "files": {
       "input": "input.html",
       "gnd": "gnd.json",
-      "utterances": "utterances.json"
-    }
+      "utterances": "utterances.json",
+      "utterancesSkipped": "utterances-skipped.json"
+    },
+    "skip": [
+      "footnote"
+    ]
   },
   {
     "id": "footnote-role-aria",
@@ -612,8 +620,12 @@
     "files": {
       "input": "input.html",
       "gnd": "gnd.json",
-      "utterances": "utterances.json"
-    }
+      "utterances": "utterances.json",
+      "utterancesSkipped": "utterances-skipped.json"
+    },
+    "skip": [
+      "footnote"
+    ]
   },
   {
     "id": "foreword-epub-type",
@@ -975,8 +987,12 @@
     "files": {
       "input": "input.html",
       "gnd": "gnd.json",
-      "utterances": "utterances.json"
-    }
+      "utterances": "utterances.json",
+      "utterancesSkipped": "utterances-skipped.json"
+    },
+    "skip": [
+      "pagebreak"
+    ]
   },
   {
     "id": "pagebreak-role-aria",
@@ -986,8 +1002,12 @@
     "files": {
       "input": "input.html",
       "gnd": "gnd.json",
-      "utterances": "utterances.json"
-    }
+      "utterances": "utterances.json",
+      "utterancesSkipped": "utterances-skipped.json"
+    },
+    "skip": [
+      "pagebreak"
+    ]
   },
   {
     "id": "pagelist-epub-type",
@@ -1022,6 +1042,61 @@
       "utterances": "utterances.json"
     }
   },
+  {
+    "id": "paragraph-block-level-language",
+    "dir": "paragraph-block-level-language",
+    "role": "paragraph",
+    "description": "Sibling paragraphs each declaring their own language, overriding the document's default",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "paragraph-document-language",
+    "dir": "paragraph-document-language",
+    "role": "paragraph",
+    "description": "A paragraph in a document whose <html lang> differs from the default, with no inline language shift or other SSML trigger",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "paragraph-multilingual-lang-attribute",
+    "dir": "paragraph-multilingual-lang-attribute",
+    "role": "paragraph",
+    "description": "An inline foreign-language phrase using the HTML lang attribute (not xml:lang) on a plain, non-semantic span",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "paragraph-multilingual-nested",
+    "dir": "paragraph-multilingual-nested",
+    "role": "paragraph",
+    "description": "A paragraph with a language switch nested inside another language switch",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
+  {
+    "id": "paragraph-multilingual-repeated-language",
+    "dir": "paragraph-multilingual-repeated-language",
+    "role": "paragraph",
+    "description": "A paragraph where the same foreign language appears twice, separated by base-language text",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
   {
     "id": "paragraph-multilingual-ssml-lang",
     "dir": "paragraph-multilingual-ssml-lang",
@@ -1033,6 +1108,17 @@
       "utterances": "utterances.json"
     }
   },
+  {
+    "id": "paragraph-multilingual-two-languages",
+    "dir": "paragraph-multilingual-two-languages",
+    "role": "paragraph",
+    "description": "A paragraph with two different inline foreign-language phrases",
+    "files": {
+      "input": "input.html",
+      "gnd": "gnd.json",
+      "utterances": "utterances.json"
+    }
+  },
   {
     "id": "part-epub-type",
     "dir": "part-epub-type",
diff --git a/fixtures/math-html-native/utterances.json b/fixtures/math-html-native/utterances.json
index 2e5d8a9..27bacc9 100644
--- a/fixtures/math-html-native/utterances.json
+++ b/fixtures/math-html-native/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "x squared plus y squared equals z squared"
+    "plain": "x squared plus y squared equals z squared"
   }
 ]
diff --git a/fixtures/math-role-aria/utterances.json b/fixtures/math-role-aria/utterances.json
index 2e5d8a9..27bacc9 100644
--- a/fixtures/math-role-aria/utterances.json
+++ b/fixtures/math-role-aria/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "x squared plus y squared equals z squared"
+    "plain": "x squared plus y squared equals z squared"
   }
 ]
diff --git a/fixtures/navigation-html-native/utterances.json b/fixtures/navigation-html-native/utterances.json
index 5cb5820..3ca8354 100644
--- a/fixtures/navigation-html-native/utterances.json
+++ b/fixtures/navigation-html-native/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "Link to the next chapter."
+    "plain": "Link to the next chapter."
   }
 ]
diff --git a/fixtures/navigation-role-aria/utterances.json b/fixtures/navigation-role-aria/utterances.json
index 5cb5820..3ca8354 100644
--- a/fixtures/navigation-role-aria/utterances.json
+++ b/fixtures/navigation-role-aria/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "Link to the next chapter."
+    "plain": "Link to the next chapter."
   }
 ]
diff --git a/fixtures/notice-epub-type/utterances.json b/fixtures/notice-epub-type/utterances.json
index b3f97c3..62cb367 100644
--- a/fixtures/notice-epub-type/utterances.json
+++ b/fixtures/notice-epub-type/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "Caution: the tower stairs are uneven."
+    "plain": "Caution: the tower stairs are uneven."
   }
 ]
diff --git a/fixtures/notice-role-aria/utterances.json b/fixtures/notice-role-aria/utterances.json
index b3f97c3..62cb367 100644
--- a/fixtures/notice-role-aria/utterances.json
+++ b/fixtures/notice-role-aria/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "Caution: the tower stairs are uneven."
+    "plain": "Caution: the tower stairs are uneven."
   }
 ]
diff --git a/fixtures/pagebreak-epub-type/meta.json b/fixtures/pagebreak-epub-type/meta.json
index bdf0f44..4428864 100644
--- a/fixtures/pagebreak-epub-type/meta.json
+++ b/fixtures/pagebreak-epub-type/meta.json
@@ -6,5 +6,6 @@
     "pagebreak"
   ],
   "sourceRef": "https://github.com/readium/guided-navigation/tree/main/examples/read-aloud",
-  "inputKind": "document"
+  "inputKind": "document",
+  "skip": ["pagebreak"]
 }
diff --git a/fixtures/pagebreak-epub-type/utterances-skipped.json b/fixtures/pagebreak-epub-type/utterances-skipped.json
new file mode 100644
index 0000000..b81f5fc
--- /dev/null
+++ b/fixtures/pagebreak-epub-type/utterances-skipped.json
@@ -0,0 +1,6 @@
+[
+  {
+    "plain": "And the next pagebreak is in the middle of a sentence.",
+    "language": "en"
+  }
+]
diff --git a/fixtures/pagebreak-epub-type/utterances.json b/fixtures/pagebreak-epub-type/utterances.json
index 9f6ab57..eb8dc68 100644
--- a/fixtures/pagebreak-epub-type/utterances.json
+++ b/fixtures/pagebreak-epub-type/utterances.json
@@ -1,11 +1,18 @@
 [
   {
-    "text": "Pagebreak. Page: 4."
+    "plain": "Pagebreak."
   },
   {
-    "text": "And the next pagebreak is in the middle of a sentence."
+    "plain": "4"
   },
   {
-    "text": "Pagebreak. Page: 5."
+    "plain": "And the next pagebreak is in the middle of a sentence.",
+    "language": "en"
+  },
+  {
+    "plain": "Pagebreak."
+  },
+  {
+    "plain": "5"
   }
 ]
diff --git a/fixtures/pagebreak-role-aria/meta.json b/fixtures/pagebreak-role-aria/meta.json
index c31359f..7599327 100644
--- a/fixtures/pagebreak-role-aria/meta.json
+++ b/fixtures/pagebreak-role-aria/meta.json
@@ -6,5 +6,6 @@
     "pagebreak"
   ],
   "sourceRef": "https://github.com/readium/guided-navigation/tree/main/examples/read-aloud",
-  "inputKind": "fragment"
+  "inputKind": "fragment",
+  "skip": ["pagebreak"]
 }
diff --git a/fixtures/pagebreak-role-aria/utterances-skipped.json b/fixtures/pagebreak-role-aria/utterances-skipped.json
new file mode 100644
index 0000000..b81f5fc
--- /dev/null
+++ b/fixtures/pagebreak-role-aria/utterances-skipped.json
@@ -0,0 +1,6 @@
+[
+  {
+    "plain": "And the next pagebreak is in the middle of a sentence.",
+    "language": "en"
+  }
+]
diff --git a/fixtures/pagebreak-role-aria/utterances.json b/fixtures/pagebreak-role-aria/utterances.json
index 9f6ab57..eb8dc68 100644
--- a/fixtures/pagebreak-role-aria/utterances.json
+++ b/fixtures/pagebreak-role-aria/utterances.json
@@ -1,11 +1,18 @@
 [
   {
-    "text": "Pagebreak. Page: 4."
+    "plain": "Pagebreak."
   },
   {
-    "text": "And the next pagebreak is in the middle of a sentence."
+    "plain": "4"
   },
   {
-    "text": "Pagebreak. Page: 5."
+    "plain": "And the next pagebreak is in the middle of a sentence.",
+    "language": "en"
+  },
+  {
+    "plain": "Pagebreak."
+  },
+  {
+    "plain": "5"
   }
 ]
diff --git a/fixtures/pagelist-epub-type/utterances.json b/fixtures/pagelist-epub-type/utterances.json
index 2702bc1..81b6af3 100644
--- a/fixtures/pagelist-epub-type/utterances.json
+++ b/fixtures/pagelist-epub-type/utterances.json
@@ -1,11 +1,11 @@
 [
   {
-    "text": "Page 1"
+    "plain": "Page 1"
   },
   {
-    "text": "Page 2"
+    "plain": "Page 2"
   },
   {
-    "text": "Page 3"
+    "plain": "Page 3"
   }
 ]
diff --git a/fixtures/pagelist-role-aria/utterances.json b/fixtures/pagelist-role-aria/utterances.json
index 2702bc1..81b6af3 100644
--- a/fixtures/pagelist-role-aria/utterances.json
+++ b/fixtures/pagelist-role-aria/utterances.json
@@ -1,11 +1,11 @@
 [
   {
-    "text": "Page 1"
+    "plain": "Page 1"
   },
   {
-    "text": "Page 2"
+    "plain": "Page 2"
   },
   {
-    "text": "Page 3"
+    "plain": "Page 3"
   }
 ]
diff --git a/fixtures/paragraph-basic/utterances.json b/fixtures/paragraph-basic/utterances.json
index 389ed63..864bf30 100644
--- a/fixtures/paragraph-basic/utterances.json
+++ b/fixtures/paragraph-basic/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "It is a truth universally acknowledged, that a single man in possession of a good fortune, must be in want of a wife."
+    "plain": "It is a truth universally acknowledged, that a single man in possession of a good fortune, must be in want of a wife."
   }
 ]
diff --git a/fixtures/paragraph-block-level-language/gnd.json b/fixtures/paragraph-block-level-language/gnd.json
new file mode 100644
index 0000000..da5c5df
--- /dev/null
+++ b/fixtures/paragraph-block-level-language/gnd.json
@@ -0,0 +1,22 @@
+{
+  "children": [
+    {
+      "role": [
+        "paragraph"
+      ],
+      "text": {
+        "plain": "Hello.",
+        "language": "en"
+      }
+    },
+    {
+      "role": [
+        "paragraph"
+      ],
+      "text": {
+        "plain": "Bonjour.",
+        "language": "fr"
+      }
+    }
+  ]
+}
diff --git a/fixtures/paragraph-block-level-language/input.html b/fixtures/paragraph-block-level-language/input.html
new file mode 100644
index 0000000..4f5a884
--- /dev/null
+++ b/fixtures/paragraph-block-level-language/input.html
@@ -0,0 +1,11 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+<meta charset="utf-8"/>
+<title>Fixture</title>
+</head>
+<body>
+<p>Hello.</p>
+<p lang="fr">Bonjour.</p>
+</body>
+</html>
diff --git a/fixtures/paragraph-block-level-language/meta.json b/fixtures/paragraph-block-level-language/meta.json
new file mode 100644
index 0000000..7e5c4d5
--- /dev/null
+++ b/fixtures/paragraph-block-level-language/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "paragraph-block-level-language",
+  "description": "Sibling paragraphs each declaring their own language, overriding the document's default",
+  "role": "paragraph",
+  "rolesCovered": [
+    "paragraph"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/tree/main/examples/read-aloud#multilingual-text",
+  "inputKind": "document"
+}
diff --git a/fixtures/paragraph-block-level-language/utterances.json b/fixtures/paragraph-block-level-language/utterances.json
new file mode 100644
index 0000000..a692582
--- /dev/null
+++ b/fixtures/paragraph-block-level-language/utterances.json
@@ -0,0 +1,10 @@
+[
+  {
+    "plain": "Hello.",
+    "language": "en"
+  },
+  {
+    "plain": "Bonjour.",
+    "language": "fr"
+  }
+]
diff --git a/fixtures/paragraph-document-language/gnd.json b/fixtures/paragraph-document-language/gnd.json
new file mode 100644
index 0000000..1e1cf83
--- /dev/null
+++ b/fixtures/paragraph-document-language/gnd.json
@@ -0,0 +1,9 @@
+{
+  "role": [
+    "paragraph"
+  ],
+  "text": {
+    "plain": "Bonjour, comment allez-vous ?",
+    "language": "fr"
+  }
+}
diff --git a/fixtures/paragraph-document-language/input.html b/fixtures/paragraph-document-language/input.html
new file mode 100644
index 0000000..1da7b42
--- /dev/null
+++ b/fixtures/paragraph-document-language/input.html
@@ -0,0 +1,10 @@
+<!DOCTYPE html>
+<html lang="fr">
+<head>
+<meta charset="utf-8"/>
+<title>Fixture</title>
+</head>
+<body>
+<p>Bonjour, comment allez-vous ?</p>
+</body>
+</html>
diff --git a/fixtures/paragraph-document-language/meta.json b/fixtures/paragraph-document-language/meta.json
new file mode 100644
index 0000000..04872be
--- /dev/null
+++ b/fixtures/paragraph-document-language/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "paragraph-document-language",
+  "description": "A paragraph in a document whose <html lang> differs from the default, with no inline language shift or other SSML trigger",
+  "role": "paragraph",
+  "rolesCovered": [
+    "paragraph"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/tree/main/examples/read-aloud#multilingual-text",
+  "inputKind": "document"
+}
diff --git a/fixtures/paragraph-document-language/utterances.json b/fixtures/paragraph-document-language/utterances.json
new file mode 100644
index 0000000..eaef74d
--- /dev/null
+++ b/fixtures/paragraph-document-language/utterances.json
@@ -0,0 +1,6 @@
+[
+  {
+    "plain": "Bonjour, comment allez-vous ?",
+    "language": "fr"
+  }
+]
diff --git a/fixtures/paragraph-multilingual-lang-attribute/gnd.json b/fixtures/paragraph-multilingual-lang-attribute/gnd.json
new file mode 100644
index 0000000..2bcf009
--- /dev/null
+++ b/fixtures/paragraph-multilingual-lang-attribute/gnd.json
@@ -0,0 +1,9 @@
+{
+  "role": [
+    "paragraph"
+  ],
+  "text": {
+    "ssml": "Hello <lang xml:lang=\"fr\">bonjour</lang>.",
+    "language": "en"
+  }
+}
diff --git a/fixtures/paragraph-multilingual-lang-attribute/input.html b/fixtures/paragraph-multilingual-lang-attribute/input.html
new file mode 100644
index 0000000..7e728a6
--- /dev/null
+++ b/fixtures/paragraph-multilingual-lang-attribute/input.html
@@ -0,0 +1 @@
+<p>Hello <span lang="fr">bonjour</span>.</p>
diff --git a/fixtures/paragraph-multilingual-lang-attribute/meta.json b/fixtures/paragraph-multilingual-lang-attribute/meta.json
new file mode 100644
index 0000000..e7834c7
--- /dev/null
+++ b/fixtures/paragraph-multilingual-lang-attribute/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "paragraph-multilingual-lang-attribute",
+  "description": "An inline foreign-language phrase using the HTML lang attribute (not xml:lang) on a plain, non-semantic span",
+  "role": "paragraph",
+  "rolesCovered": [
+    "paragraph"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/tree/main/examples/read-aloud#multilingual-text",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/paragraph-multilingual-lang-attribute/utterances.json b/fixtures/paragraph-multilingual-lang-attribute/utterances.json
new file mode 100644
index 0000000..8377dbf
--- /dev/null
+++ b/fixtures/paragraph-multilingual-lang-attribute/utterances.json
@@ -0,0 +1,6 @@
+[
+  {
+    "ssml": "Hello <lang xml:lang=\"fr\">bonjour</lang>.",
+    "language": "en"
+  }
+]
diff --git a/fixtures/paragraph-multilingual-nested/gnd.json b/fixtures/paragraph-multilingual-nested/gnd.json
new file mode 100644
index 0000000..819107a
--- /dev/null
+++ b/fixtures/paragraph-multilingual-nested/gnd.json
@@ -0,0 +1,9 @@
+{
+  "role": [
+    "paragraph"
+  ],
+  "text": {
+    "ssml": "Start <lang xml:lang=\"fr\">middle </lang><lang xml:lang=\"es\">nested</lang><lang xml:lang=\"fr\"> end</lang> after.",
+    "language": "en"
+  }
+}
diff --git a/fixtures/paragraph-multilingual-nested/input.html b/fixtures/paragraph-multilingual-nested/input.html
new file mode 100644
index 0000000..f5e691f
--- /dev/null
+++ b/fixtures/paragraph-multilingual-nested/input.html
@@ -0,0 +1 @@
+<p>Start <span xml:lang="fr">middle <span xml:lang="es">nested</span> end</span> after.</p>
diff --git a/fixtures/paragraph-multilingual-nested/meta.json b/fixtures/paragraph-multilingual-nested/meta.json
new file mode 100644
index 0000000..6c83752
--- /dev/null
+++ b/fixtures/paragraph-multilingual-nested/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "paragraph-multilingual-nested",
+  "description": "A paragraph with a language switch nested inside another language switch",
+  "role": "paragraph",
+  "rolesCovered": [
+    "paragraph"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/tree/main/examples/read-aloud#multilingual-text",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/paragraph-multilingual-nested/utterances.json b/fixtures/paragraph-multilingual-nested/utterances.json
new file mode 100644
index 0000000..e280abe
--- /dev/null
+++ b/fixtures/paragraph-multilingual-nested/utterances.json
@@ -0,0 +1,6 @@
+[
+  {
+    "ssml": "Start <lang xml:lang=\"fr\">middle </lang><lang xml:lang=\"es\">nested</lang><lang xml:lang=\"fr\"> end</lang> after.",
+    "language": "en"
+  }
+]
diff --git a/fixtures/paragraph-multilingual-repeated-language/gnd.json b/fixtures/paragraph-multilingual-repeated-language/gnd.json
new file mode 100644
index 0000000..9df021a
--- /dev/null
+++ b/fixtures/paragraph-multilingual-repeated-language/gnd.json
@@ -0,0 +1,9 @@
+{
+  "role": [
+    "paragraph"
+  ],
+  "text": {
+    "ssml": "One <lang xml:lang=\"fr\">deux</lang> three <lang xml:lang=\"fr\">quatre</lang> five.",
+    "language": "en"
+  }
+}
diff --git a/fixtures/paragraph-multilingual-repeated-language/input.html b/fixtures/paragraph-multilingual-repeated-language/input.html
new file mode 100644
index 0000000..13634ad
--- /dev/null
+++ b/fixtures/paragraph-multilingual-repeated-language/input.html
@@ -0,0 +1 @@
+<p>One <span xml:lang="fr">deux</span> three <span xml:lang="fr">quatre</span> five.</p>
diff --git a/fixtures/paragraph-multilingual-repeated-language/meta.json b/fixtures/paragraph-multilingual-repeated-language/meta.json
new file mode 100644
index 0000000..9364db6
--- /dev/null
+++ b/fixtures/paragraph-multilingual-repeated-language/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "paragraph-multilingual-repeated-language",
+  "description": "A paragraph where the same foreign language appears twice, separated by base-language text",
+  "role": "paragraph",
+  "rolesCovered": [
+    "paragraph"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/tree/main/examples/read-aloud#multilingual-text",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/paragraph-multilingual-repeated-language/utterances.json b/fixtures/paragraph-multilingual-repeated-language/utterances.json
new file mode 100644
index 0000000..9d89c44
--- /dev/null
+++ b/fixtures/paragraph-multilingual-repeated-language/utterances.json
@@ -0,0 +1,6 @@
+[
+  {
+    "ssml": "One <lang xml:lang=\"fr\">deux</lang> three <lang xml:lang=\"fr\">quatre</lang> five.",
+    "language": "en"
+  }
+]
diff --git a/fixtures/paragraph-multilingual-ssml-lang/utterances.json b/fixtures/paragraph-multilingual-ssml-lang/utterances.json
index 30f8c91..e675f8b 100644
--- a/fixtures/paragraph-multilingual-ssml-lang/utterances.json
+++ b/fixtures/paragraph-multilingual-ssml-lang/utterances.json
@@ -1,7 +1,6 @@
 [
   {
-    "text": "This job requires a certain <lang xml:lang=\"fr\">savoir faire</lang> that can only be acquired over time.",
-    "ssml": true,
+    "ssml": "This job requires a certain <lang xml:lang=\"fr\">savoir faire</lang> that can only be acquired over time.",
     "language": "en"
   }
 ]
diff --git a/fixtures/paragraph-multilingual-two-languages/gnd.json b/fixtures/paragraph-multilingual-two-languages/gnd.json
new file mode 100644
index 0000000..9fdc27e
--- /dev/null
+++ b/fixtures/paragraph-multilingual-two-languages/gnd.json
@@ -0,0 +1,9 @@
+{
+  "role": [
+    "paragraph"
+  ],
+  "text": {
+    "ssml": "Hello <lang xml:lang=\"fr\">bonjour</lang> and <lang xml:lang=\"es\">hola</lang> there.",
+    "language": "en"
+  }
+}
diff --git a/fixtures/paragraph-multilingual-two-languages/input.html b/fixtures/paragraph-multilingual-two-languages/input.html
new file mode 100644
index 0000000..a957261
--- /dev/null
+++ b/fixtures/paragraph-multilingual-two-languages/input.html
@@ -0,0 +1 @@
+<p>Hello <em xml:lang="fr">bonjour</em> and <em xml:lang="es">hola</em> there.</p>
diff --git a/fixtures/paragraph-multilingual-two-languages/meta.json b/fixtures/paragraph-multilingual-two-languages/meta.json
new file mode 100644
index 0000000..c609342
--- /dev/null
+++ b/fixtures/paragraph-multilingual-two-languages/meta.json
@@ -0,0 +1,10 @@
+{
+  "id": "paragraph-multilingual-two-languages",
+  "description": "A paragraph with two different inline foreign-language phrases",
+  "role": "paragraph",
+  "rolesCovered": [
+    "paragraph"
+  ],
+  "sourceRef": "https://github.com/readium/guided-navigation/tree/main/examples/read-aloud#multilingual-text",
+  "inputKind": "fragment"
+}
diff --git a/fixtures/paragraph-multilingual-two-languages/utterances.json b/fixtures/paragraph-multilingual-two-languages/utterances.json
new file mode 100644
index 0000000..a3986d0
--- /dev/null
+++ b/fixtures/paragraph-multilingual-two-languages/utterances.json
@@ -0,0 +1,6 @@
+[
+  {
+    "ssml": "Hello <lang xml:lang=\"fr\">bonjour</lang> and <lang xml:lang=\"es\">hola</lang> there.",
+    "language": "en"
+  }
+]
diff --git a/fixtures/part-epub-type/utterances.json b/fixtures/part-epub-type/utterances.json
index 0f3abff..61814f5 100644
--- a/fixtures/part-epub-type/utterances.json
+++ b/fixtures/part-epub-type/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "Title of the part"
+    "plain": "Title of the part"
   }
 ]
diff --git a/fixtures/part-role-aria/utterances.json b/fixtures/part-role-aria/utterances.json
index 0f3abff..61814f5 100644
--- a/fixtures/part-role-aria/utterances.json
+++ b/fixtures/part-role-aria/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "Title of the part"
+    "plain": "Title of the part"
   }
 ]
diff --git a/fixtures/preface-epub-type/utterances.json b/fixtures/preface-epub-type/utterances.json
index 72b6951..d6aa5e8 100644
--- a/fixtures/preface-epub-type/utterances.json
+++ b/fixtures/preface-epub-type/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "This edition adds a chapter on automation."
+    "plain": "This edition adds a chapter on automation."
   }
 ]
diff --git a/fixtures/preface-role-aria/utterances.json b/fixtures/preface-role-aria/utterances.json
index 72b6951..d6aa5e8 100644
--- a/fixtures/preface-role-aria/utterances.json
+++ b/fixtures/preface-role-aria/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "This edition adds a chapter on automation."
+    "plain": "This edition adds a chapter on automation."
   }
 ]
diff --git a/fixtures/preformatted-html-native/utterances.json b/fixtures/preformatted-html-native/utterances.json
index 4658e91..4165e9f 100644
--- a/fixtures/preformatted-html-native/utterances.json
+++ b/fixtures/preformatted-html-native/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "10 PRINT \"HELLO\" 20 GOTO 10"
+    "plain": "10 PRINT \"HELLO\" 20 GOTO 10"
   }
 ]
diff --git a/fixtures/presentation-role-aria/utterances.json b/fixtures/presentation-role-aria/utterances.json
index c369476..a80ff25 100644
--- a/fixtures/presentation-role-aria/utterances.json
+++ b/fixtures/presentation-role-aria/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "Decorative content with no semantic meaning."
+    "plain": "Decorative content with no semantic meaning."
   }
 ]
diff --git a/fixtures/prologue-epub-type/utterances.json b/fixtures/prologue-epub-type/utterances.json
index d246a2e..024b3e7 100644
--- a/fixtures/prologue-epub-type/utterances.json
+++ b/fixtures/prologue-epub-type/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "Before the lamp was ever lit, the rock was already feared."
+    "plain": "Before the lamp was ever lit, the rock was already feared."
   }
 ]
diff --git a/fixtures/prologue-role-aria/utterances.json b/fixtures/prologue-role-aria/utterances.json
index d246a2e..024b3e7 100644
--- a/fixtures/prologue-role-aria/utterances.json
+++ b/fixtures/prologue-role-aria/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "Before the lamp was ever lit, the rock was already feared."
+    "plain": "Before the lamp was ever lit, the rock was already feared."
   }
 ]
diff --git a/fixtures/pullquote-epub-type/utterances.json b/fixtures/pullquote-epub-type/utterances.json
index bbbf7ab..d2d00eb 100644
--- a/fixtures/pullquote-epub-type/utterances.json
+++ b/fixtures/pullquote-epub-type/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "The lamp still turns, though no one climbs the stairs anymore."
+    "plain": "The lamp still turns, though no one climbs the stairs anymore."
   }
 ]
diff --git a/fixtures/pullquote-role-aria/utterances.json b/fixtures/pullquote-role-aria/utterances.json
index bbbf7ab..d2d00eb 100644
--- a/fixtures/pullquote-role-aria/utterances.json
+++ b/fixtures/pullquote-role-aria/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "The lamp still turns, though no one climbs the stairs anymore."
+    "plain": "The lamp still turns, though no one climbs the stairs anymore."
   }
 ]
diff --git a/fixtures/qna-epub-type/utterances.json b/fixtures/qna-epub-type/utterances.json
index 6b8def2..254ec25 100644
--- a/fixtures/qna-epub-type/utterances.json
+++ b/fixtures/qna-epub-type/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "Q: How often was the lamp refueled? A: Nightly, by hand."
+    "plain": "Q: How often was the lamp refueled? A: Nightly, by hand."
   }
 ]
diff --git a/fixtures/qna-role-aria/utterances.json b/fixtures/qna-role-aria/utterances.json
index 6b8def2..254ec25 100644
--- a/fixtures/qna-role-aria/utterances.json
+++ b/fixtures/qna-role-aria/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "Q: How often was the lamp refueled? A: Nightly, by hand."
+    "plain": "Q: How often was the lamp refueled? A: Nightly, by hand."
   }
 ]
diff --git a/fixtures/region-role-aria/utterances.json b/fixtures/region-role-aria/utterances.json
index 1b71593..a3e3271 100644
--- a/fixtures/region-role-aria/utterances.json
+++ b/fixtures/region-role-aria/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "A named region of interest within the page."
+    "plain": "A named region of interest within the page."
   }
 ]
diff --git a/fixtures/section-html-native/utterances.json b/fixtures/section-html-native/utterances.json
index 0842118..eb94260 100644
--- a/fixtures/section-html-native/utterances.json
+++ b/fixtures/section-html-native/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "The lighthouse was decommissioned in 1998, though its light still functions as a private aid to navigation."
+    "plain": "The lighthouse was decommissioned in 1998, though its light still functions as a private aid to navigation."
   }
 ]
diff --git a/fixtures/separator-html-native/utterances.json b/fixtures/separator-html-native/utterances.json
index 3dbb778..da51e76 100644
--- a/fixtures/separator-html-native/utterances.json
+++ b/fixtures/separator-html-native/utterances.json
@@ -1,8 +1,8 @@
 [
   {
-    "text": "Section one."
+    "plain": "Section one."
   },
   {
-    "text": "Section two."
+    "plain": "Section two."
   }
 ]
diff --git a/fixtures/separator-role-aria/utterances.json b/fixtures/separator-role-aria/utterances.json
index 3dbb778..da51e76 100644
--- a/fixtures/separator-role-aria/utterances.json
+++ b/fixtures/separator-role-aria/utterances.json
@@ -1,8 +1,8 @@
 [
   {
-    "text": "Section one."
+    "plain": "Section one."
   },
   {
-    "text": "Section two."
+    "plain": "Section two."
   }
 ]
diff --git a/fixtures/subtitle-epub-type/utterances.json b/fixtures/subtitle-epub-type/utterances.json
index deaf58a..b162db7 100644
--- a/fixtures/subtitle-epub-type/utterances.json
+++ b/fixtures/subtitle-epub-type/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "A History of Coastal Lights"
+    "plain": "A History of Coastal Lights"
   }
 ]
diff --git a/fixtures/subtitle-role-aria/utterances.json b/fixtures/subtitle-role-aria/utterances.json
index deaf58a..b162db7 100644
--- a/fixtures/subtitle-role-aria/utterances.json
+++ b/fixtures/subtitle-role-aria/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "A History of Coastal Lights"
+    "plain": "A History of Coastal Lights"
   }
 ]
diff --git a/fixtures/summary-html-native/utterances.json b/fixtures/summary-html-native/utterances.json
index fd1cc76..61a9134 100644
--- a/fixtures/summary-html-native/utterances.json
+++ b/fixtures/summary-html-native/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "Click to expand"
+    "plain": "Click to expand"
   }
 ]
diff --git a/fixtures/table-html-native/utterances.json b/fixtures/table-html-native/utterances.json
index bcc7105..1e8b76c 100644
--- a/fixtures/table-html-native/utterances.json
+++ b/fixtures/table-html-native/utterances.json
@@ -1,20 +1,20 @@
 [
   {
-    "text": "Name"
+    "plain": "Name"
   },
   {
-    "text": "Role"
+    "plain": "Role"
   },
   {
-    "text": "Ada"
+    "plain": "Ada"
   },
   {
-    "text": "Engineer"
+    "plain": "Engineer"
   },
   {
-    "text": "Grace"
+    "plain": "Grace"
   },
   {
-    "text": "Admiral"
+    "plain": "Admiral"
   }
 ]
diff --git a/fixtures/table-role-aria/utterances.json b/fixtures/table-role-aria/utterances.json
index bcc7105..1e8b76c 100644
--- a/fixtures/table-role-aria/utterances.json
+++ b/fixtures/table-role-aria/utterances.json
@@ -1,20 +1,20 @@
 [
   {
-    "text": "Name"
+    "plain": "Name"
   },
   {
-    "text": "Role"
+    "plain": "Role"
   },
   {
-    "text": "Ada"
+    "plain": "Ada"
   },
   {
-    "text": "Engineer"
+    "plain": "Engineer"
   },
   {
-    "text": "Grace"
+    "plain": "Grace"
   },
   {
-    "text": "Admiral"
+    "plain": "Admiral"
   }
 ]
diff --git a/fixtures/term-epub-type/utterances.json b/fixtures/term-epub-type/utterances.json
index c008575..5194285 100644
--- a/fixtures/term-epub-type/utterances.json
+++ b/fixtures/term-epub-type/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "lighthouse"
+    "plain": "lighthouse"
   }
 ]
diff --git a/fixtures/term-html-native/utterances.json b/fixtures/term-html-native/utterances.json
index c008575..5194285 100644
--- a/fixtures/term-html-native/utterances.json
+++ b/fixtures/term-html-native/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "lighthouse"
+    "plain": "lighthouse"
   }
 ]
diff --git a/fixtures/term-role-aria/utterances.json b/fixtures/term-role-aria/utterances.json
index c008575..5194285 100644
--- a/fixtures/term-role-aria/utterances.json
+++ b/fixtures/term-role-aria/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "lighthouse"
+    "plain": "lighthouse"
   }
 ]
diff --git a/fixtures/tip-epub-type/utterances.json b/fixtures/tip-epub-type/utterances.json
index 0af016d..50ed99a 100644
--- a/fixtures/tip-epub-type/utterances.json
+++ b/fixtures/tip-epub-type/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "Tip: wind the mechanism fully before dusk."
+    "plain": "Tip: wind the mechanism fully before dusk."
   }
 ]
diff --git a/fixtures/tip-role-aria/utterances.json b/fixtures/tip-role-aria/utterances.json
index 0af016d..50ed99a 100644
--- a/fixtures/tip-role-aria/utterances.json
+++ b/fixtures/tip-role-aria/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "Tip: wind the mechanism fully before dusk."
+    "plain": "Tip: wind the mechanism fully before dusk."
   }
 ]
diff --git a/fixtures/toc-epub-type/utterances.json b/fixtures/toc-epub-type/utterances.json
index 492da85..3f1861e 100644
--- a/fixtures/toc-epub-type/utterances.json
+++ b/fixtures/toc-epub-type/utterances.json
@@ -1,11 +1,11 @@
 [
   {
-    "text": "Chapter One"
+    "plain": "Chapter One"
   },
   {
-    "text": "Chapter Two"
+    "plain": "Chapter Two"
   },
   {
-    "text": "Chapter Three"
+    "plain": "Chapter Three"
   }
 ]
diff --git a/fixtures/toc-role-aria/utterances.json b/fixtures/toc-role-aria/utterances.json
index 492da85..3f1861e 100644
--- a/fixtures/toc-role-aria/utterances.json
+++ b/fixtures/toc-role-aria/utterances.json
@@ -1,11 +1,11 @@
 [
   {
-    "text": "Chapter One"
+    "plain": "Chapter One"
   },
   {
-    "text": "Chapter Two"
+    "plain": "Chapter Two"
   },
   {
-    "text": "Chapter Three"
+    "plain": "Chapter Three"
   }
 ]
diff --git a/fixtures/video-html-native/utterances.json b/fixtures/video-html-native/utterances.json
index 401af4a..352df36 100644
--- a/fixtures/video-html-native/utterances.json
+++ b/fixtures/video-html-native/utterances.json
@@ -1,5 +1,5 @@
 [
   {
-    "text": "The lamp mechanism rotating at dusk"
+    "plain": "The lamp mechanism rotating at dusk"
   }
 ]
diff --git a/package.json b/package.json
index 405cd17..84e7b6f 100644
--- a/package.json
+++ b/package.json
@@ -39,6 +39,7 @@
     "test": "npm run build && NODE_NO_WARNINGS=1 ava test/**/*.test.ts",
     "test:voices": "npm run build && NODE_NO_WARNINGS=1 ava test/WebSpeechVoiceManager/*.test.ts",
     "test:gnd": "NODE_NO_WARNINGS=1 ava test/gnd/*.test.ts",
+    "test:utterances": "NODE_NO_WARNINGS=1 ava test/utterances/*.test.ts",
     "generate-metadata": "node scripts/generate-metadata.js",
     "generate-fixtures-manifest": "node scripts/build-fixtures-manifest.js",
     "clean": "rimraf ./build",
diff --git a/scripts/build-fixtures-manifest.js b/scripts/build-fixtures-manifest.js
index 1f8fff1..65b122f 100644
--- a/scripts/build-fixtures-manifest.js
+++ b/scripts/build-fixtures-manifest.js
@@ -32,8 +32,11 @@ const manifest = fixtureIds.map((id) => {
   if (meta.id !== id) {
     throw new Error(`fixtures/${id}/meta.json has id "${meta.id}", expected "${id}"`);
   }
+  if (meta.skip && !fs.existsSync(path.join(dir, "utterances-skipped.json"))) {
+    throw new Error(`fixtures/${id} sets meta.skip but is missing utterances-skipped.json`);
+  }
 
-  return {
+  const entry = {
     id,
     dir: id,
     role: meta.role,
@@ -44,6 +47,11 @@ const manifest = fixtureIds.map((id) => {
       utterances: "utterances.json",
     },
   };
+  if (meta.skip) {
+    entry.skip = meta.skip;
+    entry.files.utterancesSkipped = "utterances-skipped.json";
+  }
+  return entry;
 });
 
 const ids = manifest.map((e) => e.id);
diff --git a/src/WebSpeech/webSpeechEngine.ts b/src/WebSpeech/webSpeechEngine.ts
index e4d5a60..44d8ea6 100644
--- a/src/WebSpeech/webSpeechEngine.ts
+++ b/src/WebSpeech/webSpeechEngine.ts
@@ -136,18 +136,19 @@ export class WebSpeechEngine implements ReadiumSpeechPlaybackEngine {
     return this.currentVoice;
   }
 
-  // SSML Escaping
-  private escapeSSML(utterances: ReadiumSpeechUtterance[]): ReadiumSpeechUtterance[] {
+  // Web Speech API has no SSML support: use the authored plain text, falling
+  // back to a tag-stripped rendering of the SSML only when no plain
+  // alternative was provided by the source.
+  private toPlainText(utterances: ReadiumSpeechUtterance[]): ReadiumSpeechUtterance[] {
     return utterances.map(content => ({
       ...content,
-      text: content.ssml ? stripHtml(content.text).result : content.text
+      plain: content.plain ?? (content.ssml ? stripHtml(content.ssml).result : "")
     }));
   }
 
   // Queue Management
   loadUtterances(contents: ReadiumSpeechUtterance[]): void {
-    // Escape SSML entirely for the time being
-    this.currentUtterances = this.escapeSSML(contents);
+    this.currentUtterances = this.toPlainText(contents);
     this.currentUtteranceIndex = 0;
     this.setState("ready");
     this.emitEvent({ type: "ready" });
@@ -261,7 +262,7 @@ export class WebSpeechEngine implements ReadiumSpeechPlaybackEngine {
     }
 
     const content = this.currentUtterances[this.currentUtteranceIndex];
-    const text = content.ssml ? content.text : content.text;
+    const text = content.plain ?? "";
 
     // Validate text length
     this.validateText(text);
diff --git a/src/gnd/converter.ts b/src/gnd/converter.ts
index 6e6c57f..a380ddc 100644
--- a/src/gnd/converter.ts
+++ b/src/gnd/converter.ts
@@ -610,7 +610,7 @@ export class Converter {
  * Converts the children of an HTML or XHTML fragment or document's <body>
  * into Guided Navigation objects.
  */
-export function convert(input: string, mediaType?: GndMediaType): GndNode[] {
+export function parseMarkup(input: string, mediaType?: GndMediaType): GndNode[] {
   const mt = mediaType ?? sniffMediaType(input);
   const doc = new DOMParser().parseFromString(input, mt);
   const body = doc.querySelector("body");
diff --git a/src/gnd/index.ts b/src/gnd/index.ts
index 89f6b72..da1c3dc 100644
--- a/src/gnd/index.ts
+++ b/src/gnd/index.ts
@@ -1,4 +1,4 @@
 export type { GndRole, GndTextAlternative, GndNode, GndDocument } from "./types.js";
-export { parseGnd } from "./parseGnd.js";
-export { convert } from "./converter.js";
+export { makeGnd } from "./makeGnd.js";
+export { parseMarkup } from "./converter.js";
 export type { GndMediaType } from "./dom.js";
diff --git a/src/gnd/parseGnd.ts b/src/gnd/makeGnd.ts
similarity index 58%
rename from src/gnd/parseGnd.ts
rename to src/gnd/makeGnd.ts
index 3270568..2728844 100644
--- a/src/gnd/parseGnd.ts
+++ b/src/gnd/makeGnd.ts
@@ -1,15 +1,15 @@
 import type { GndDocument } from "./types.js";
-import { convert } from "./converter.js";
+import { parseMarkup } from "./converter.js";
 import type { GndMediaType } from "./dom.js";
 
 export type { GndMediaType };
 
 /**
- * Parses an HTML or XHTML fragment or document into a Guided Navigation
+ * Builds a Guided Navigation document from an HTML or XHTML fragment or
  * document, following https://github.com/readium/guided-navigation.
  */
-export function parseGnd(input: string, mediaType?: GndMediaType): GndDocument {
-  const children = convert(input, mediaType);
+export function makeGnd(input: string, mediaType?: GndMediaType): GndDocument {
+  const children = parseMarkup(input, mediaType);
   const body: GndDocument["guided"][number] = { role: ["body"] };
   if (children.length > 0) body.children = children;
   return { guided: [body] };
diff --git a/src/index.ts b/src/index.ts
index eba65d0..97885ea 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -10,4 +10,5 @@ export * from "./engine";
 export * from "./navigator";
 export * from "./provider";
 export * from "./utterance";
-export * from "./gnd";
\ No newline at end of file
+export * from "./gnd";
+export * from "./utterances";
\ No newline at end of file
diff --git a/src/utterance.ts b/src/utterance.ts
index 1ab4978..ae798f0 100644
--- a/src/utterance.ts
+++ b/src/utterance.ts
@@ -1,6 +1,6 @@
 export interface ReadiumSpeechUtterance {
-  id?: string;          // Unique identifier for this content
-  text: string;         // Text or SSML content
-  ssml?: boolean;       // If true, text contains SSML
-  language?: string;    // Language of this content (BCP 47)
+  id?: string;           // Unique identifier for this content
+  plain?: string;        // Plain-text rendering, when available
+  ssml?: string;         // SSML rendering, when available
+  language?: string;     // Language of this content (BCP 47)
 }
\ No newline at end of file
diff --git a/src/utterances/announcements.ts b/src/utterances/announcements.ts
new file mode 100644
index 0000000..7513221
--- /dev/null
+++ b/src/utterances/announcements.ts
@@ -0,0 +1,12 @@
+import type { Announcements } from "./types.js";
+
+// Default English announcement catalog. Expect this to grow considerably as
+// more roles gain contextualizing announcements (see `AnnouncementKey`);
+// callers can override or extend any subset of these keys via
+// `ExtractUtterancesOptions.announcements`, e.g. once localized catalogs
+// (Weblate-sourced) become available.
+export const defaultAnnouncements: Announcements = {
+  footnoteStart: "Start of the footnote.",
+  footnoteEnd: "End of the footnote.",
+  pagebreak: "Pagebreak.",
+};
diff --git a/src/utterances/extractUtterances.ts b/src/utterances/extractUtterances.ts
new file mode 100644
index 0000000..ce69f67
--- /dev/null
+++ b/src/utterances/extractUtterances.ts
@@ -0,0 +1,98 @@
+import type { GndNode, GndRole } from "../gnd/types.js";
+import type { ReadiumSpeechUtterance } from "../utterance.js";
+import { defaultAnnouncements } from "./announcements.js";
+import { resolveNodeText } from "./text.js";
+import type { Announcement, Announcements, ExtractUtterancesOptions } from "./types.js";
+
+function resolveAnnouncement(announcement: Announcement, params?: Record<string, string>): string {
+  return typeof announcement === "function" ? announcement(params) : announcement;
+}
+
+function pushAnnouncement(
+  out: ReadiumSpeechUtterance[],
+  announcements: Announcements,
+  key: string,
+  params?: Record<string, string>,
+): void {
+  const announcement = announcements[key];
+  if (announcement === undefined) return;
+  out.push({ plain: resolveAnnouncement(announcement, params) });
+}
+
+function isSkipped(roles: GndRole[], skip: ReadonlySet<GndRole>): boolean {
+  return skip.size > 0 && roles.some((role) => skip.has(role));
+}
+
+function walk(
+  nodes: GndNode[],
+  out: ReadiumSpeechUtterance[],
+  announcements: Announcements,
+  skip: ReadonlySet<GndRole>,
+): void {
+  for (const node of nodes) {
+    const roles = node.role ?? [];
+    if (isSkipped(roles, skip)) continue;
+
+    // A noteref's own visible text (e.g. "[1]") is a visual marker only,
+    // never spoken. Its footnote target is announced with a start/end pair
+    // around its normal extraction; any other kind of child is walked as-is.
+    if (roles.includes("noteref")) {
+      for (const child of node.children ?? []) {
+        const childRoles = child.role ?? [];
+        if (isSkipped(childRoles, skip)) continue;
+        if (childRoles.includes("footnote")) {
+          pushAnnouncement(out, announcements, "footnoteStart");
+          walk([child], out, announcements, skip);
+          pushAnnouncement(out, announcements, "footnoteEnd");
+        } else {
+          walk([child], out, announcements, skip);
+        }
+      }
+      continue;
+    }
+
+    const resolved = resolveNodeText(node.text);
+    if (resolved) {
+      // Only the "pagebreak" announcement itself is templated. The
+      // pagebreak's own label (from its `title`) is arbitrary author-supplied
+      // text — it might already read as "Page 5" or a roman numeral — so it's
+      // spoken as-is, not wrapped in a template that risks saying "page"
+      // twice or otherwise mangling it.
+      if (roles.includes("pagebreak")) {
+        pushAnnouncement(out, announcements, "pagebreak");
+      }
+      const utterance: ReadiumSpeechUtterance = {};
+      if (resolved.plain) utterance.plain = resolved.plain;
+      if (resolved.ssml) utterance.ssml = resolved.ssml;
+      if (resolved.language) utterance.language = resolved.language;
+      out.push(utterance);
+    }
+
+    if (node.children) walk(node.children, out, announcements, skip);
+
+    // A description is supplementary/elaborating content (e.g. an extended
+    // audio description), spoken after the primary content it describes.
+    if (node.description !== undefined) {
+      out.push({ plain: node.description });
+    }
+  }
+}
+
+/**
+ * Extracts an ordered list of read-aloud utterances from a Guided
+ * Navigation node tree, following the patterns documented at
+ * https://github.com/readium/guided-navigation/tree/main/examples/read-aloud.
+ *
+ * Accepts `GndNode[]` (as returned by `parseMarkup()`, or `GndDocument.guided`)
+ * rather than a wrapped document.
+ */
+export function extractUtterances(
+  nodes: GndNode[],
+  options?: ExtractUtterancesOptions,
+): ReadiumSpeechUtterance[] {
+  const announcements: Announcements = { ...defaultAnnouncements, ...options?.announcements };
+  const skip = new Set(options?.skip ?? []);
+  const out: ReadiumSpeechUtterance[] = [];
+  walk(nodes, out, announcements, skip);
+  return out;
+}
diff --git a/src/utterances/index.ts b/src/utterances/index.ts
new file mode 100644
index 0000000..67de521
--- /dev/null
+++ b/src/utterances/index.ts
@@ -0,0 +1,3 @@
+export { extractUtterances } from "./extractUtterances.js";
+export { skippableRoles } from "./roles.js";
+export type { Announcement, AnnouncementKey, Announcements, ExtractUtterancesOptions } from "./types.js";
diff --git a/src/utterances/roles.ts b/src/utterances/roles.ts
new file mode 100644
index 0000000..b6289db
--- /dev/null
+++ b/src/utterances/roles.ts
@@ -0,0 +1,26 @@
+import type { GndRole } from "../gnd/types.js";
+
+// https://github.com/readium/guided-navigation/blob/main/roles.md#list-of-skippable-roles
+// Roles a reader may choose to skip past during playback — ancillary
+// content (asides, footnotes...) and navigational aids (tables of
+// contents, page lists...) that aren't part of the primary reading flow.
+// Nothing is skipped by default: pass a subset of this list (or all of
+// it) via `ExtractUtterancesOptions.skip` to opt in.
+export const skippableRoles: GndRole[] = [
+  // Ancillary content
+  "aside",
+  "bibliography",
+  "details",
+  "endnotes",
+  "footnote",
+  "noteref",
+  "pullquote",
+  // Navigation
+  "landmarks",
+  "loa",
+  "loi",
+  "lot",
+  "lov",
+  "pagebreak",
+  "toc",
+];
diff --git a/src/utterances/text.ts b/src/utterances/text.ts
new file mode 100644
index 0000000..9af335f
--- /dev/null
+++ b/src/utterances/text.ts
@@ -0,0 +1,79 @@
+import { startsWithBindingPunct } from "../gnd/text.js";
+import type { GndNode } from "../gnd/types.js";
+
+export interface ResolvedNodeText {
+  plain?: string;
+  ssml?: string;
+  language?: string;
+}
+
+// Matches a `<readium:TAG id="...">` self-closing placeholder (see
+// `flushText()` in `../gnd/converter.ts`), along with any surrounding
+// whitespace so it can be removed as a whole unit.
+const PLACEHOLDER_RE = /\s*<readium:[a-zA-Z][\w-]*\s+id="[^"]*"\s*\/>\s*/g;
+
+/**
+ * Removes `<readium:TAG id="...">` placeholders from an SSML string. These
+ * mark where an embedded reference (a noteref, pagebreak, image...) sits in
+ * the text flow, linking to a sibling/child GND object by id — real GND
+ * consumers resolve them from there. This extractor instead speaks that
+ * referenced object as its own separate utterance (via the normal children
+ * walk), so the placeholder itself is just removed, using the same
+ * binding-punctuation rule the GND converter itself uses when omitting a
+ * placeholder from its plain-text variant (see `startsWithBindingPunct` in
+ * `../gnd/text.ts`): no space is inserted before punctuation that binds to
+ * the preceding word (e.g. ".", ","), but a single space is inserted
+ * between two words that would otherwise run together.
+ */
+function stripPlaceholders(ssml: string): string {
+  const stripped = ssml.replace(PLACEHOLDER_RE, (match, offset: number, str: string) => {
+    const after = str.slice(offset + match.length);
+    return after.length === 0 || startsWithBindingPunct(after) ? "" : " ";
+  });
+  return stripped.replace(/ {2,}/g, " ").trim();
+}
+
+// A `<` can only appear in an SSML string as the start of a real SSML tag —
+// any literal `<` in the source text itself is entity-escaped by the GND
+// converter. So once placeholders are stripped, this is a reliable check for
+// whether any actual SSML markup (`<lang>`, `<emphasis>`, `<break/>`...)
+// remains, as opposed to a placeholder-only string that's now redundant with
+// the `plain` variant (which the GND converter guarantees is present
+// whenever the only reason `ssml` existed was an embedded placeholder — see
+// `converter.ts`'s `hasPlaceholder` handling).
+function hasSsmlMarkup(s: string): boolean {
+  return s.includes("<");
+}
+
+/**
+ * Resolves a `GndNode.text` value (a plain string, or a `GndTextAlternative`
+ * carrying separate plain/SSML variants) into the shape an utterance needs.
+ *
+ * Mirrors the Readium text object as-is: `plain` and `ssml` are independent
+ * alternatives, not one derived from the other, so both are passed through
+ * whenever the source provides both (e.g. a footnote reference, where the
+ * SSML carries an embedded `<readium:noteref>` placeholder and the plain
+ * variant already omits it). The SSML variant gets `stripPlaceholders`
+ * applied first, since this extractor speaks referenced objects (noterefs,
+ * pagebreaks) separately via the normal children walk rather than inline —
+ * and if stripping a placeholder leaves no actual SSML markup behind, `ssml`
+ * is dropped entirely rather than reported as a duplicate of `plain`.
+ *
+ * `language` is carried alongside either variant: the GND converter attaches
+ * the nearest ancestor's declared language (e.g. `<html lang="fr">`) to every
+ * text node under it, so this is the only place that document-declared
+ * language would otherwise be lost.
+ */
+export function resolveNodeText(text: GndNode["text"]): ResolvedNodeText | undefined {
+  if (text === undefined) return undefined;
+  if (typeof text === "string") return { plain: text };
+
+  const result: ResolvedNodeText = { language: text.language };
+  if (text.ssml) {
+    const stripped = stripPlaceholders(text.ssml);
+    if (hasSsmlMarkup(stripped)) result.ssml = stripped;
+  }
+  if (text.plain) result.plain = text.plain;
+
+  return result.plain || result.ssml ? result : undefined;
+}
diff --git a/src/utterances/types.ts b/src/utterances/types.ts
new file mode 100644
index 0000000..942ac24
--- /dev/null
+++ b/src/utterances/types.ts
@@ -0,0 +1,27 @@
+import type { GndRole } from "../gnd/types.js";
+
+// Announcements are synthesized, navigational text the extractor adds to
+// contextualize an utterance (e.g. entering/leaving a footnote, a pagebreak
+// marker) — as opposed to content utterances, which speak text found in the
+// document itself. The catalog of announcement keys is expected to grow
+// substantially as more roles gain contextualizing announcements, so it's
+// kept as a plain string rather than a closed union — same rationale as
+// `GndRole` in `../gnd/types.js`.
+export type AnnouncementKey = string;
+
+export type Announcement = string | ((params?: Record<string, string>) => string);
+
+export type Announcements = Record<AnnouncementKey, Announcement>;
+
+export interface ExtractUtterancesOptions {
+  // A plain string index signature (not `Partial<Announcements>`): callers
+  // can supply any subset of keys, known or new, without needing an
+  // `| undefined` on every value.
+  announcements?: Announcements;
+
+  // Roles to omit entirely (the node and its whole subtree) from the
+  // output, e.g. so a reader can skip past footnotes or navigational aids
+  // during playback. See `skippableRoles` for the roles.md-documented set.
+  // Nothing is skipped by default (`[]`).
+  skip?: GndRole[];
+}
diff --git a/test/gnd/fixtures.test.ts b/test/gnd/fixtures.test.ts
index bd5cbd1..e97a012 100644
--- a/test/gnd/fixtures.test.ts
+++ b/test/gnd/fixtures.test.ts
@@ -1,7 +1,7 @@
 import "./setup.js";
 import test from "ava";
 import { loadManifest, loadFixture } from "../testUtils.js";
-import { convert } from "../../src/gnd/converter.js";
+import { parseMarkup } from "../../src/gnd/converter.js";
 
 const manifest = loadManifest();
 
@@ -30,7 +30,7 @@ function sortKeysDeep(value: unknown): unknown {
 
 // gnd.json stores a single fixture's expected top-level item(s) directly —
 // a bare object for one item, or a role-less/id-less `{children: [...]}` for
-// several siblings — while `convert()` always returns an array. This maps
+// several siblings — while `parseMarkup()` always returns an array. This maps
 // the stored file format onto that array shape for comparison.
 function expectedTopLevel(gnd: unknown): unknown[] {
   if (gnd && typeof gnd === "object" && !Array.isArray(gnd)) {
@@ -43,9 +43,9 @@ function expectedTopLevel(gnd: unknown): unknown[] {
 }
 
 // <body> is always the traversal root, never content in its own right, so
-// convert() never produces a "body"-rolebearing object for it to check
+// parseMarkup() never produces a "body"-rolebearing object for it to check
 // against — this fixture documents the expected role mapping but can't be
-// exercised through convert(); it's excluded from that check only.
+// exercised through parseMarkup(); it's excluded from that check only.
 const excludedFromConvertCheck = new Set(["body-html-native"]);
 
 for (const entry of manifest) {
@@ -67,14 +67,17 @@ for (const entry of manifest) {
     t.true(Array.isArray(fixture.utterances), "utterances.json must parse to an array");
     for (const utterance of fixture.utterances as Record<string, unknown>[]) {
       t.true(typeof utterance === "object" && utterance !== null);
-      t.true(typeof utterance.text === "string", "each utterance needs a text field");
+      t.true(
+        typeof utterance.plain === "string" || typeof utterance.ssml === "string",
+        "each utterance needs a plain or ssml field",
+      );
     }
   });
 
   if (!excludedFromConvertCheck.has(entry.id)) {
-    test(`fixture "${entry.id}": convert matches gnd.json`, (t) => {
+    test(`fixture "${entry.id}": parseMarkup matches gnd.json`, (t) => {
       const fixture = loadFixture(entry.id);
-      const actual = convert(fixture.inputHtml);
+      const actual = parseMarkup(fixture.inputHtml);
       t.deepEqual(sortKeysDeep(actual), sortKeysDeep(expectedTopLevel(fixture.gnd)));
     });
   }
diff --git a/test/testUtils.ts b/test/testUtils.ts
index 277788f..8c30d5a 100644
--- a/test/testUtils.ts
+++ b/test/testUtils.ts
@@ -20,10 +20,12 @@ export interface FixtureManifestEntry {
   dir: string;
   role: string;
   description: string;
+  skip?: string[];
   files: {
     input: string;
     gnd: string;
     utterances: string;
+    utterancesSkipped?: string;
   };
 }
 
@@ -34,6 +36,7 @@ export interface FixtureMeta {
   rolesCovered: string[];
   sourceRef: string;
   inputKind: "fragment" | "document";
+  skip?: string[];
 }
 
 export interface LoadedFixture {
@@ -41,6 +44,7 @@ export interface LoadedFixture {
   inputHtml: string;
   gnd: unknown;
   utterances: unknown[];
+  utterancesSkipped?: unknown[];
 }
 
 const fixturesDir = join(__dirname, "../fixtures");
@@ -61,5 +65,8 @@ export function loadFixture(id: string): LoadedFixture {
   const inputHtml = readFileSync(join(dir, "input.html"), "utf-8");
   const gnd = JSON.parse(readFileSync(join(dir, "gnd.json"), "utf-8"));
   const utterances = JSON.parse(readFileSync(join(dir, "utterances.json"), "utf-8"));
-  return { meta, inputHtml, gnd, utterances };
+  const utterancesSkipped = meta.skip
+    ? JSON.parse(readFileSync(join(dir, "utterances-skipped.json"), "utf-8"))
+    : undefined;
+  return { meta, inputHtml, gnd, utterances, utterancesSkipped };
 }
diff --git a/test/utterances/fixtures.test.ts b/test/utterances/fixtures.test.ts
new file mode 100644
index 0000000..2fd6875
--- /dev/null
+++ b/test/utterances/fixtures.test.ts
@@ -0,0 +1,38 @@
+import "../gnd/setup.js";
+import test from "ava";
+import { loadManifest, loadFixture } from "../testUtils.js";
+import { parseMarkup } from "../../src/gnd/converter.js";
+import { extractUtterances } from "../../src/utterances/extractUtterances.js";
+
+const manifest = loadManifest();
+
+function sortKeysDeep(value: unknown): unknown {
+  if (Array.isArray(value)) return value.map(sortKeysDeep);
+  if (value && typeof value === "object") {
+    return Object.keys(value)
+      .sort()
+      .reduce((acc: Record<string, unknown>, key) => {
+        acc[key] = sortKeysDeep((value as Record<string, unknown>)[key]);
+        return acc;
+      }, {});
+  }
+  return value;
+}
+
+for (const entry of manifest) {
+  test(`fixture "${entry.id}": extractUtterances matches utterances.json`, (t) => {
+    const fixture = loadFixture(entry.id);
+    const gnd = parseMarkup(fixture.inputHtml);
+    const actual = extractUtterances(gnd);
+    t.deepEqual(sortKeysDeep(actual), sortKeysDeep(fixture.utterances));
+  });
+
+  if (entry.skip) {
+    test(`fixture "${entry.id}": extractUtterances with skip matches utterances-skipped.json`, (t) => {
+      const fixture = loadFixture(entry.id);
+      const gnd = parseMarkup(fixture.inputHtml);
+      const actual = extractUtterances(gnd, { skip: entry.skip });
+      t.deepEqual(sortKeysDeep(actual), sortKeysDeep(fixture.utterancesSkipped));
+    });
+  }
+}
diff --git a/test/utterances/skip.test.ts b/test/utterances/skip.test.ts
new file mode 100644
index 0000000..aa46ee8
--- /dev/null
+++ b/test/utterances/skip.test.ts
@@ -0,0 +1,28 @@
+import test from "ava";
+import { skippableRoles } from "../../src/utterances/roles.js";
+
+// Behavioral skip coverage (footnote/aside/pagebreak/...) lives in the
+// shared fixtures suite (fixtures/*/utterances-skipped.json, driven by
+// test/utterances/fixtures.test.ts) so other platform ports get it too.
+// This only checks the TS-specific convenience export against the spec.
+test("skippableRoles matches the roles.md skippable-roles list", (t) => {
+  t.deepEqual(
+    [...skippableRoles].sort(),
+    [
+      "aside",
+      "bibliography",
+      "details",
+      "endnotes",
+      "footnote",
+      "landmarks",
+      "loa",
+      "loi",
+      "lot",
+      "lov",
+      "noteref",
+      "pagebreak",
+      "pullquote",
+      "toc",
+    ].sort(),
+  );
+});

From de70374ce4411a7e8ac72134369b37b066cf6f61 Mon Sep 17 00:00:00 2001
From: Jiminy Panoz <JayPanoz@users.noreply.github.com>
Date: Mon, 13 Jul 2026 17:58:59 +0200
Subject: [PATCH 7/7] option-based utterances

---
 demo/playground/index.html                    |  29 +++
 demo/playground/script.js                     | 143 ++++++++---
 demo/playground/styles.css                    |  50 ++++
 fixtures/README.md                            | 134 ++++++----
 fixtures/abstract-epub-type/gnd.json          |  11 +-
 .../{input.html => input.xhtml}               |   0
 fixtures/abstract-epub-type/utterances.json   |  49 +++-
 fixtures/abstract-role-aria/utterances.json   |  49 +++-
 fixtures/acknowledgments-epub-type/gnd.json   |  11 +-
 .../{input.html => input.xhtml}               |   0
 .../acknowledgments-epub-type/utterances.json |  55 +++-
 .../acknowledgments-role-aria/utterances.json |  55 +++-
 fixtures/afterword-epub-type/gnd.json         |  11 +-
 .../{input.html => input.xhtml}               |   0
 fixtures/afterword-epub-type/utterances.json  |  55 +++-
 fixtures/afterword-role-aria/utterances.json  |  55 +++-
 fixtures/appendix-epub-type/gnd.json          |  13 +-
 .../{input.html => input.xhtml}               |   0
 fixtures/appendix-epub-type/utterances.json   |  55 +++-
 fixtures/appendix-role-aria/utterances.json   |  55 +++-
 fixtures/article-html-native/utterances.json  |  19 +-
 fixtures/aside-html-native/meta.json          |   3 +-
 .../aside-html-native/utterances-skipped.json |   1 -
 fixtures/aside-html-native/utterances.json    |  71 +++++-
 fixtures/audio-html-native/utterances.json    |  19 +-
 fixtures/backlink-epub-type/gnd.json          |  13 +-
 .../{input.html => input.xhtml}               |   0
 fixtures/backlink-epub-type/utterances.json   |  19 +-
 fixtures/backlink-role-aria/utterances.json   |  19 +-
 fixtures/bibliography-epub-type/gnd.json      |  29 ++-
 .../{input.html => input.xhtml}               |   0
 .../bibliography-epub-type/utterances.json    |  84 ++++++-
 .../bibliography-role-aria/utterances.json    |  84 ++++++-
 fixtures/biblioref-epub-type/gnd.json         |  13 +-
 .../{input.html => input.xhtml}               |   0
 fixtures/biblioref-epub-type/utterances.json  |  19 +-
 fixtures/biblioref-role-aria/utterances.json  |  19 +-
 .../blockquote-html-native/utterances.json    |  19 +-
 fixtures/body-html-native/utterances.json     |  19 +-
 fixtures/chapter-epub-type/gnd.json           |  15 +-
 .../{input.html => input.xhtml}               |   0
 fixtures/chapter-epub-type/utterances.json    |  61 ++++-
 fixtures/chapter-role-aria/utterances.json    |  61 ++++-
 fixtures/colophon-epub-type/gnd.json          |  11 +-
 .../{input.html => input.xhtml}               |   0
 fixtures/colophon-epub-type/utterances.json   |  49 +++-
 fixtures/colophon-role-aria/utterances.json   |  49 +++-
 .../complementary-role-aria/utterances.json   |  19 +-
 fixtures/conclusion-epub-type/gnd.json        |  11 +-
 .../{input.html => input.xhtml}               |   0
 fixtures/conclusion-epub-type/utterances.json |  55 +++-
 fixtures/conclusion-role-aria/utterances.json |  55 +++-
 fixtures/cover-epub-type/gnd.json             |  17 +-
 .../{input.html => input.xhtml}               |   0
 fixtures/cover-epub-type/utterances.json      |  49 +++-
 fixtures/cover-role-aria/utterances.json      |  49 +++-
 fixtures/credit-epub-type/gnd.json            |  13 +-
 .../{input.html => input.xhtml}               |   0
 fixtures/credit-epub-type/utterances.json     |  49 +++-
 fixtures/credit-role-aria/utterances.json     |  49 +++-
 fixtures/credits-epub-type/gnd.json           |  37 +--
 .../{input.html => input.xhtml}               |   0
 fixtures/credits-epub-type/utterances.json    |  80 +++++-
 fixtures/credits-role-aria/utterances.json    |  80 +++++-
 fixtures/dedication-epub-type/gnd.json        |  11 +-
 .../{input.html => input.xhtml}               |   0
 fixtures/dedication-epub-type/utterances.json |  49 +++-
 fixtures/dedication-role-aria/utterances.json |  49 +++-
 fixtures/definition-epub-type/gnd.json        |  13 +-
 .../{input.html => input.xhtml}               |   0
 fixtures/definition-epub-type/utterances.json |  55 +++-
 .../definition-html-native/utterances.json    |  19 +-
 fixtures/definition-role-aria/utterances.json |  19 +-
 fixtures/details-html-native/utterances.json  |  71 +++++-
 fixtures/endnotes-epub-type/gnd.json          |  47 ++--
 .../{input.html => input.xhtml}               |   0
 fixtures/endnotes-epub-type/utterances.json   | 144 ++++++++++-
 fixtures/endnotes-role-aria/utterances.json   | 114 ++++++++-
 fixtures/epigraph-epub-type/gnd.json          |  11 +-
 .../{input.html => input.xhtml}               |   0
 fixtures/epigraph-epub-type/utterances.json   |  49 +++-
 fixtures/epigraph-role-aria/utterances.json   |  49 +++-
 fixtures/epilogue-epub-type/gnd.json          |  11 +-
 .../{input.html => input.xhtml}               |   0
 fixtures/epilogue-epub-type/utterances.json   |  55 +++-
 fixtures/epilogue-role-aria/utterances.json   |  55 +++-
 fixtures/errata-epub-type/gnd.json            |  11 +-
 .../{input.html => input.xhtml}               |   0
 fixtures/errata-epub-type/utterances.json     |  49 +++-
 fixtures/errata-role-aria/utterances.json     |  49 +++-
 fixtures/example-epub-type/gnd.json           |  11 +-
 .../{input.html => input.xhtml}               |   0
 fixtures/example-epub-type/utterances.json    |  49 +++-
 fixtures/example-role-aria/utterances.json    |  49 +++-
 fixtures/figure-basic-epub-type/gnd.json      |  15 +-
 .../{input.html => input.xhtml}               |   0
 .../figure-basic-epub-type/utterances.json    |  55 +++-
 .../figure-basic-html-native/utterances.json  |  55 +++-
 .../figure-basic-role-aria/utterances.json    |  55 +++-
 .../utterances.json                           |  55 +++-
 .../figure-caption-role-aria/utterances.json  |  55 +++-
 fixtures/figure-describedby/utterances.json   |  68 ++++-
 fixtures/footnote-epub-type/gnd.json          |  21 +-
 .../{input.html => input.xhtml}               |   0
 fixtures/footnote-epub-type/meta.json         |   3 +-
 .../utterances-skipped.json                   |   6 -
 fixtures/footnote-epub-type/utterances.json   | 205 ++++++++++++++-
 fixtures/footnote-role-aria/meta.json         |   3 +-
 .../utterances-skipped.json                   |   6 -
 fixtures/footnote-role-aria/utterances.json   | 205 ++++++++++++++-
 fixtures/foreword-epub-type/gnd.json          |  11 +-
 .../{input.html => input.xhtml}               |   0
 fixtures/foreword-epub-type/utterances.json   |  19 +-
 fixtures/foreword-role-aria/utterances.json   |  19 +-
 fixtures/glossary-epub-type/gnd.json          |  49 ++--
 .../{input.html => input.xhtml}               |   0
 fixtures/glossary-epub-type/utterances.json   |  98 +++++++-
 fixtures/glossary-role-aria/utterances.json   |  98 +++++++-
 fixtures/glossref-epub-type/gnd.json          |  13 +-
 .../{input.html => input.xhtml}               |   0
 fixtures/glossref-epub-type/utterances.json   |  19 +-
 fixtures/glossref-role-aria/utterances.json   |  19 +-
 fixtures/header-html-native/utterances.json   |  19 +-
 fixtures/heading-html-native/utterances.json  | 152 +++++++++--
 fixtures/heading-role-aria/utterances.json    | 152 +++++++++--
 .../image-alt-html-native/utterances.json     |  19 +-
 .../utterances.json                           |  26 +-
 .../utterances.json                           |  26 +-
 fixtures/image-role-aria/utterances.json      |  19 +-
 fixtures/index-epub-type/gnd.json             |  33 ++-
 .../{input.html => input.xhtml}               |   0
 fixtures/index-epub-type/utterances.json      |  68 ++++-
 fixtures/index-role-aria/utterances.json      |  68 ++++-
 fixtures/introduction-epub-type/gnd.json      |  11 +-
 .../{input.html => input.xhtml}               |   0
 .../introduction-epub-type/utterances.json    |  55 +++-
 .../introduction-role-aria/utterances.json    |  55 +++-
 fixtures/landmarks-epub-type/gnd.json         |  47 ++--
 .../{input.html => input.xhtml}               |   0
 fixtures/landmarks-epub-type/utterances.json  |  99 +++++++-
 fixtures/list-html-native/utterances.json     |  35 ++-
 fixtures/list-role-aria/utterances.json       |  35 ++-
 fixtures/loa-epub-type/gnd.json               |  33 ++-
 .../loa-epub-type/{input.html => input.xhtml} |   0
 fixtures/loa-epub-type/utterances.json        |  84 ++++++-
 fixtures/loi-epub-type/gnd.json               |  33 ++-
 .../loi-epub-type/{input.html => input.xhtml} |   0
 fixtures/loi-epub-type/utterances.json        |  84 ++++++-
 fixtures/lot-epub-type/gnd.json               |  33 ++-
 .../lot-epub-type/{input.html => input.xhtml} |   0
 fixtures/lot-epub-type/utterances.json        |  84 ++++++-
 fixtures/lov-epub-type/gnd.json               |  33 ++-
 .../lov-epub-type/{input.html => input.xhtml} |   0
 fixtures/lov-epub-type/utterances.json        |  84 ++++++-
 fixtures/main-html-native/utterances.json     |  19 +-
 fixtures/main-role-aria/utterances.json       |  19 +-
 fixtures/manifest.json                        | 128 ++++------
 fixtures/math-html-native/utterances.json     |  19 +-
 fixtures/math-role-aria/utterances.json       |  19 +-
 .../navigation-html-native/utterances.json    |  19 +-
 fixtures/navigation-role-aria/utterances.json |  19 +-
 fixtures/notice-epub-type/gnd.json            |  11 +-
 .../{input.html => input.xhtml}               |   0
 fixtures/notice-epub-type/utterances.json     |  49 +++-
 fixtures/notice-role-aria/utterances.json     |  49 +++-
 fixtures/pagebreak-epub-type/gnd.json         |  23 +-
 .../{input.html => input.xhtml}               |   0
 fixtures/pagebreak-epub-type/meta.json        |   3 +-
 .../utterances-skipped.json                   |   6 -
 fixtures/pagebreak-epub-type/utterances.json  | 174 +++++++++++--
 fixtures/pagebreak-role-aria/meta.json        |   3 +-
 .../utterances-skipped.json                   |   6 -
 fixtures/pagebreak-role-aria/utterances.json  | 174 +++++++++++--
 fixtures/pagelist-epub-type/gnd.json          |  47 ++--
 .../{input.html => input.xhtml}               |   0
 fixtures/pagelist-epub-type/utterances.json   |  83 ++++++-
 fixtures/pagelist-role-aria/utterances.json   |  83 ++++++-
 fixtures/paragraph-basic/utterances.json      |  19 +-
 .../paragraph-block-level-language/gnd.json   |  23 +-
 .../utterances.json                           |  62 ++++-
 fixtures/paragraph-document-language/gnd.json |  17 +-
 .../utterances.json                           |  46 +++-
 .../utterances.json                           |  57 ++++-
 .../utterances.json                           |  57 ++++-
 .../utterances.json                           |  57 ++++-
 .../utterances.json                           |  57 ++++-
 .../utterances.json                           |  57 ++++-
 fixtures/part-epub-type/gnd.json              |  15 +-
 .../{input.html => input.xhtml}               |   0
 fixtures/part-epub-type/utterances.json       |  61 ++++-
 fixtures/part-role-aria/utterances.json       |  61 ++++-
 fixtures/preface-epub-type/gnd.json           |  11 +-
 .../{input.html => input.xhtml}               |   0
 fixtures/preface-epub-type/utterances.json    |  55 +++-
 fixtures/preface-role-aria/utterances.json    |  55 +++-
 .../preformatted-html-native/utterances.json  |  19 +-
 .../presentation-role-aria/utterances.json    |  19 +-
 fixtures/prologue-epub-type/gnd.json          |  11 +-
 .../{input.html => input.xhtml}               |   0
 fixtures/prologue-epub-type/utterances.json   |  55 +++-
 fixtures/prologue-role-aria/utterances.json   |  55 +++-
 fixtures/pullquote-epub-type/gnd.json         |  13 +-
 .../{input.html => input.xhtml}               |   0
 fixtures/pullquote-epub-type/utterances.json  |  93 ++++++-
 fixtures/pullquote-role-aria/utterances.json  |  65 ++++-
 fixtures/qna-epub-type/gnd.json               |  13 +-
 .../qna-epub-type/{input.html => input.xhtml} |   0
 fixtures/qna-epub-type/utterances.json        |  55 +++-
 fixtures/qna-role-aria/utterances.json        |  55 +++-
 fixtures/region-role-aria/utterances.json     |  19 +-
 fixtures/section-html-native/utterances.json  |  19 +-
 .../separator-html-native/utterances.json     |  26 +-
 fixtures/separator-role-aria/utterances.json  |  26 +-
 fixtures/subtitle-epub-type/gnd.json          |  11 +-
 .../{input.html => input.xhtml}               |   0
 fixtures/subtitle-epub-type/utterances.json   |  49 +++-
 fixtures/subtitle-role-aria/utterances.json   |  49 +++-
 fixtures/summary-html-native/utterances.json  |  19 +-
 fixtures/table-html-native/utterances.json    | 128 ++++++++--
 fixtures/table-role-aria/utterances.json      | 128 ++++++++--
 fixtures/term-epub-type/gnd.json              |  13 +-
 .../{input.html => input.xhtml}               |   0
 fixtures/term-epub-type/utterances.json       |  55 +++-
 fixtures/term-html-native/utterances.json     |  19 +-
 fixtures/term-role-aria/utterances.json       |  19 +-
 fixtures/tip-epub-type/gnd.json               |  13 +-
 .../tip-epub-type/{input.html => input.xhtml} |   0
 fixtures/tip-epub-type/utterances.json        |  77 +++++-
 fixtures/tip-role-aria/utterances.json        |  49 +++-
 fixtures/toc-epub-type/gnd.json               |  47 ++--
 .../toc-epub-type/{input.html => input.xhtml} |   0
 fixtures/toc-epub-type/utterances.json        |  99 +++++++-
 fixtures/toc-role-aria/utterances.json        |  99 +++++++-
 fixtures/video-html-native/utterances.json    |  19 +-
 package.json                                  |   1 +
 scripts/build-fixtures-manifest.js            |  15 +-
 scripts/generate-utterances.js                |  99 ++++++++
 src/gnd/converter.ts                          |  24 +-
 src/gnd/makeGnd.ts                            |   5 +-
 src/utterances/announcements.ts               |  72 +++++-
 src/utterances/extractUtterances.ts           | 235 ++++++++++++++----
 src/utterances/index.ts                       |  10 +-
 src/utterances/language.ts                    |   9 +
 src/utterances/text.ts                        |  54 ++++
 src/utterances/types.ts                       |  75 +++++-
 test/gnd/fixtures.test.ts                     |  45 ++--
 test/gnd/makeGnd.test.ts                      |  20 ++
 test/testUtils.ts                             |  38 ++-
 test/utterances/fixtures.test.ts              |  26 +-
 249 files changed, 8158 insertions(+), 1336 deletions(-)
 rename fixtures/abstract-epub-type/{input.html => input.xhtml} (100%)
 rename fixtures/acknowledgments-epub-type/{input.html => input.xhtml} (100%)
 rename fixtures/afterword-epub-type/{input.html => input.xhtml} (100%)
 rename fixtures/appendix-epub-type/{input.html => input.xhtml} (100%)
 delete mode 100644 fixtures/aside-html-native/utterances-skipped.json
 rename fixtures/backlink-epub-type/{input.html => input.xhtml} (100%)
 rename fixtures/bibliography-epub-type/{input.html => input.xhtml} (100%)
 rename fixtures/biblioref-epub-type/{input.html => input.xhtml} (100%)
 rename fixtures/chapter-epub-type/{input.html => input.xhtml} (100%)
 rename fixtures/colophon-epub-type/{input.html => input.xhtml} (100%)
 rename fixtures/conclusion-epub-type/{input.html => input.xhtml} (100%)
 rename fixtures/cover-epub-type/{input.html => input.xhtml} (100%)
 rename fixtures/credit-epub-type/{input.html => input.xhtml} (100%)
 rename fixtures/credits-epub-type/{input.html => input.xhtml} (100%)
 rename fixtures/dedication-epub-type/{input.html => input.xhtml} (100%)
 rename fixtures/definition-epub-type/{input.html => input.xhtml} (100%)
 rename fixtures/endnotes-epub-type/{input.html => input.xhtml} (100%)
 rename fixtures/epigraph-epub-type/{input.html => input.xhtml} (100%)
 rename fixtures/epilogue-epub-type/{input.html => input.xhtml} (100%)
 rename fixtures/errata-epub-type/{input.html => input.xhtml} (100%)
 rename fixtures/example-epub-type/{input.html => input.xhtml} (100%)
 rename fixtures/figure-basic-epub-type/{input.html => input.xhtml} (100%)
 rename fixtures/footnote-epub-type/{input.html => input.xhtml} (100%)
 delete mode 100644 fixtures/footnote-epub-type/utterances-skipped.json
 delete mode 100644 fixtures/footnote-role-aria/utterances-skipped.json
 rename fixtures/foreword-epub-type/{input.html => input.xhtml} (100%)
 rename fixtures/glossary-epub-type/{input.html => input.xhtml} (100%)
 rename fixtures/glossref-epub-type/{input.html => input.xhtml} (100%)
 rename fixtures/index-epub-type/{input.html => input.xhtml} (100%)
 rename fixtures/introduction-epub-type/{input.html => input.xhtml} (100%)
 rename fixtures/landmarks-epub-type/{input.html => input.xhtml} (100%)
 rename fixtures/loa-epub-type/{input.html => input.xhtml} (100%)
 rename fixtures/loi-epub-type/{input.html => input.xhtml} (100%)
 rename fixtures/lot-epub-type/{input.html => input.xhtml} (100%)
 rename fixtures/lov-epub-type/{input.html => input.xhtml} (100%)
 rename fixtures/notice-epub-type/{input.html => input.xhtml} (100%)
 rename fixtures/pagebreak-epub-type/{input.html => input.xhtml} (100%)
 delete mode 100644 fixtures/pagebreak-epub-type/utterances-skipped.json
 delete mode 100644 fixtures/pagebreak-role-aria/utterances-skipped.json
 rename fixtures/pagelist-epub-type/{input.html => input.xhtml} (100%)
 rename fixtures/part-epub-type/{input.html => input.xhtml} (100%)
 rename fixtures/preface-epub-type/{input.html => input.xhtml} (100%)
 rename fixtures/prologue-epub-type/{input.html => input.xhtml} (100%)
 rename fixtures/pullquote-epub-type/{input.html => input.xhtml} (100%)
 rename fixtures/qna-epub-type/{input.html => input.xhtml} (100%)
 rename fixtures/subtitle-epub-type/{input.html => input.xhtml} (100%)
 rename fixtures/term-epub-type/{input.html => input.xhtml} (100%)
 rename fixtures/tip-epub-type/{input.html => input.xhtml} (100%)
 rename fixtures/toc-epub-type/{input.html => input.xhtml} (100%)
 create mode 100644 scripts/generate-utterances.js
 create mode 100644 src/utterances/language.ts
 create mode 100644 test/gnd/makeGnd.test.ts

diff --git a/demo/playground/index.html b/demo/playground/index.html
index 3a83216..aca4a7c 100644
--- a/demo/playground/index.html
+++ b/demo/playground/index.html
@@ -45,6 +45,35 @@ <h3>Actual</h3>
         <h2>3. Utterances</h2>
         <span id="utterances-badge" class="badge"></span>
       </div>
+
+      <div id="utterances-options" class="options-bar">
+        <fieldset class="options-group">
+          <legend>Format</legend>
+          <label><input type="radio" name="format" value="plain" checked> plain</label>
+          <label><input type="radio" name="format" value="ssml"> ssml</label>
+        </fieldset>
+
+        <fieldset class="options-group">
+          <legend>Language</legend>
+          <select id="option-language">
+            <option value="">(default)</option>
+            <option value="never">never</option>
+            <option value="block">block</option>
+            <option value="inline">inline</option>
+          </select>
+        </fieldset>
+
+        <fieldset class="options-group">
+          <label><input type="checkbox" id="option-interrupt"> interruptSentence</label>
+          <label><input type="checkbox" id="option-contextualize" checked> contextualize</label>
+        </fieldset>
+
+        <fieldset class="options-group">
+          <legend>Skip roles</legend>
+          <select id="option-skip" multiple></select>
+        </fieldset>
+      </div>
+
       <div class="compare-grid">
         <div>
           <h3>Expected</h3>
diff --git a/demo/playground/script.js b/demo/playground/script.js
index 38aa728..7495b0f 100644
--- a/demo/playground/script.js
+++ b/demo/playground/script.js
@@ -8,6 +8,11 @@ const gndBadgeEl = document.getElementById("gnd-badge");
 const utterancesExpectedEl = document.getElementById("utterances-expected");
 const utterancesActualEl = document.getElementById("utterances-actual");
 const utterancesBadgeEl = document.getElementById("utterances-badge");
+const optionSkipEl = document.getElementById("option-skip");
+const optionLanguageEl = document.getElementById("option-language");
+const optionInterruptEl = document.getElementById("option-interrupt");
+const optionContextualizeEl = document.getElementById("option-contextualize");
+const formatRadios = [...document.querySelectorAll('input[name="format"]')];
 
 // Feature-detect the GND converter and the utterance extractor, if/when
 // @readium/speech exports them.
@@ -15,14 +20,58 @@ let converter = null;
 let utteranceExtractor = null;
 try {
   const mod = await import("../../build/index.js");
-  if (typeof mod.convert === "function") {
+  if (typeof mod.parseMarkup === "function") {
     converter = mod;
   }
   if (typeof mod.extractUtterances === "function") {
     utteranceExtractor = mod;
   }
-} catch {
-  // build/index.js may not export these yet; that's expected pre-implementation.
+  if (Array.isArray(mod.skippableRoles)) {
+    for (const role of mod.skippableRoles) {
+      const option = document.createElement("option");
+      option.value = role;
+      option.textContent = role;
+      optionSkipEl.appendChild(option);
+    }
+    optionSkipEl.addEventListener("change", () => renderUtterances());
+  }
+} catch (err) {
+  // build/index.js may not exist yet (run `npm run build`) or may not
+  // export these yet; logged rather than silently swallowed so a real
+  // failure here doesn't just look like an empty options list.
+  console.error("Failed to load @readium/speech build/index.js:", err);
+}
+
+// The extraction options currently selected in the toolbar, beyond the
+// required `format` — mirrors exactly how fixtures/*/utterances.json's
+// `variants[].options` are shaped, so it can be compared against them
+// directly (see `matchingExpected`).
+function currentExtraOptions() {
+  const extra = {};
+  const skip = optionSkipEl
+    ? [...optionSkipEl.selectedOptions].map((option) => option.value)
+    : [];
+  if (skip.length > 0) extra.skip = skip;
+  if (optionLanguageEl?.value) extra.language = optionLanguageEl.value;
+  if (optionInterruptEl?.checked) extra.interruptSentence = true;
+  if (optionContextualizeEl && !optionContextualizeEl.checked) extra.contextualize = false;
+  return extra;
+}
+
+function currentFormat() {
+  return formatRadios.find((r) => r.checked)?.value ?? "plain";
+}
+
+// Finds the fixture's expected output for the exact combination of options
+// currently selected: the branch's `base` when no extra options are set, or
+// the `variants` entry whose `options` deep-equals the selection. Returns
+// `undefined` when this fixture doesn't illustrate that combination.
+function matchingExpected(utterances, format, extraOptions) {
+  const branch = utterances[format];
+  if (!branch) return undefined;
+  if (Object.keys(extraOptions).length === 0) return branch.base;
+  const variant = (branch.variants ?? []).find((v) => deepEqual(v.options, extraOptions));
+  return variant?.utterances;
 }
 
 const manifest = await fetch("../../fixtures/manifest.json").then((r) => r.json());
@@ -138,7 +187,7 @@ function withSchemaKeyOrder(value) {
 
 // gnd.json stores a single fixture's expected top-level item(s) directly —
 // a bare object for one item, or a role-less/id-less `{children: [...]}` for
-// several siblings — while `convert()` always returns an array. This maps
+// several siblings — while `parseMarkup()` always returns an array. This maps
 // the stored file format onto that array shape for comparison.
 function expectedTopLevel(gnd) {
   if (gnd && typeof gnd === "object" && !Array.isArray(gnd)) {
@@ -148,18 +197,52 @@ function expectedTopLevel(gnd) {
   return [gnd];
 }
 
-// Inverse of expectedTopLevel: reshapes convert()'s array output into the
-// same bare-object/`{children}` convention gnd.json is stored in, so the
-// "actual" pane displays in the fixture's own reference shape.
+// Inverse of expectedTopLevel: reshapes parseMarkup()'s array output into
+// the same bare-object/`{children}` convention gnd.json is stored in, so
+// the "actual" pane displays in the fixture's own reference shape.
 function toStoredShape(items) {
   return items.length === 1 ? items[0] : { children: items };
 }
 
 function setBadge(el, state) {
-  el.textContent = state === "pass" ? "pass" : state === "fail" ? "fail" : "not implemented yet";
+  el.textContent =
+    state === "pass" ? "pass" : state === "fail" ? "fail" : state === "none" ? "no fixture data for this combination" : "not implemented yet";
   el.className = `badge ${state}`;
 }
 
+// Cached across options-toolbar changes, so toggling an option re-runs
+// extraction without refetching the fixture's files.
+let currentFixture = null;
+
+function renderUtterances() {
+  if (!currentFixture) return;
+  const { gndActual, utterances } = currentFixture;
+  const format = currentFormat();
+  const extraOptions = currentExtraOptions();
+  const expected = matchingExpected(utterances, format, extraOptions);
+
+  utterancesExpectedEl.textContent =
+    expected !== undefined ? JSON.stringify(expected, null, 2) : "(none — this fixture doesn't illustrate this combination of options)";
+
+  if (!utteranceExtractor || gndActual === undefined) {
+    utterancesActualEl.textContent = "";
+    setBadge(utterancesBadgeEl, "pending");
+    return;
+  }
+
+  try {
+    const actualUtterances = utteranceExtractor.extractUtterances(gndActual, { format, ...extraOptions });
+    utterancesActualEl.textContent = JSON.stringify(actualUtterances, null, 2);
+    setBadge(
+      utterancesBadgeEl,
+      expected === undefined ? "none" : deepEqual(actualUtterances, expected) ? "pass" : "fail",
+    );
+  } catch (err) {
+    utterancesActualEl.textContent = String(err);
+    setBadge(utterancesBadgeEl, "fail");
+  }
+}
+
 async function selectFixture(id) {
   selectedId = id;
   for (const li of fixtureListEl.querySelectorAll("li[data-id]")) {
@@ -189,42 +272,30 @@ async function selectFixture(id) {
 
   inputHtmlEl.textContent = inputHtml;
   gndExpectedEl.textContent = JSON.stringify(withSchemaKeyOrder(gnd), null, 2);
-  utterancesExpectedEl.textContent = JSON.stringify(utterances, null, 2);
 
+  let gndActual;
   if (!converter) {
     gndActualEl.textContent = "";
     setBadge(gndBadgeEl, "pending");
-    utterancesActualEl.textContent = "";
-    setBadge(utterancesBadgeEl, "pending");
-    return;
-  }
-
-  let actual;
-  try {
-    actual = converter.convert(inputHtml);
-    gndActualEl.textContent = JSON.stringify(withSchemaKeyOrder(toStoredShape(actual)), null, 2);
-    setBadge(gndBadgeEl, deepEqual(actual, expectedTopLevel(gnd)) ? "pass" : "fail");
-  } catch (err) {
-    gndActualEl.textContent = String(err);
-    setBadge(gndBadgeEl, "fail");
-  }
-
-  if (!utteranceExtractor || actual === undefined) {
-    utterancesActualEl.textContent = "";
-    setBadge(utterancesBadgeEl, "pending");
-    return;
+  } else {
+    try {
+      gndActual = converter.parseMarkup(inputHtml);
+      gndActualEl.textContent = JSON.stringify(withSchemaKeyOrder(toStoredShape(gndActual)), null, 2);
+      setBadge(gndBadgeEl, deepEqual(gndActual, expectedTopLevel(gnd)) ? "pass" : "fail");
+    } catch (err) {
+      gndActualEl.textContent = String(err);
+      setBadge(gndBadgeEl, "fail");
+    }
   }
 
-  try {
-    const actualUtterances = utteranceExtractor.extractUtterances(actual);
-    utterancesActualEl.textContent = JSON.stringify(actualUtterances, null, 2);
-    setBadge(utterancesBadgeEl, deepEqual(actualUtterances, utterances) ? "pass" : "fail");
-  } catch (err) {
-    utterancesActualEl.textContent = String(err);
-    setBadge(utterancesBadgeEl, "fail");
-  }
+  currentFixture = { gndActual, utterances };
+  renderUtterances();
 }
 
 filterInput.addEventListener("input", renderList);
+for (const radio of formatRadios) radio.addEventListener("change", renderUtterances);
+optionLanguageEl?.addEventListener("change", renderUtterances);
+optionInterruptEl?.addEventListener("change", renderUtterances);
+optionContextualizeEl?.addEventListener("change", renderUtterances);
 
 renderList();
diff --git a/demo/playground/styles.css b/demo/playground/styles.css
index 981e426..905990d 100644
--- a/demo/playground/styles.css
+++ b/demo/playground/styles.css
@@ -163,6 +163,56 @@ body {
   margin: 0;
 }
 
+.options-bar {
+  display: flex;
+  flex-wrap: wrap;
+  gap: 16px;
+  margin: 10px 0 14px;
+  padding: 10px 12px;
+  border: 1px solid #ddd;
+  border-radius: 6px;
+  background: #fafafa;
+}
+
+.options-group {
+  display: flex;
+  flex-wrap: wrap;
+  align-items: center;
+  gap: 4px 10px;
+  border: none;
+  margin: 0;
+  padding: 0;
+}
+
+.options-group legend {
+  font-size: 0.78em;
+  font-weight: 600;
+  color: #666;
+  padding: 0 4px 0 0;
+}
+
+.options-group label {
+  font-size: 0.85em;
+  white-space: nowrap;
+}
+
+#option-skip {
+  /* <select multiple> inside a `display: flex` <fieldset> is a known
+     cross-browser sizing trap — fieldsets don't reliably compute a flex
+     child's intrinsic size, so the select can collapse to near-zero
+     width despite min-width. `flex: none` plus an explicit `width`
+     (not just `min-width`) sidesteps that entirely. */
+  flex: none;
+  width: 180px;
+  height: 5.5em;
+  font-size: 0.85em;
+}
+
+.badge.none {
+  background: #fff3cd;
+  color: #856404;
+}
+
 .compare-grid {
   display: grid;
   grid-template-columns: 1fr 1fr;
diff --git a/fixtures/README.md b/fixtures/README.md
index 14c660e..6ed4c33 100644
--- a/fixtures/README.md
+++ b/fixtures/README.md
@@ -26,11 +26,13 @@ fixtures/
   ROLES_COVERAGE.md       flat list of every role covered and its fixtures (generated — do not hand-edit)
   <fixture-id>/
     meta.json             fixture metadata
-    input.html             the HTML input (a fragment or a full document, see meta.json.inputKind)
-    gnd.json               the expected Guided Navigation document produced from input.html
-    utterances.json        the expected ordered utterance list produced from gnd.json
-    utterances-skipped.json  only present when meta.json.skip is set — the expected
-                             utterance list when skipping the role(s) listed there
+    input.html             the input markup as HTML (a fragment or a full document, see meta.json.inputKind);
+                            or input.xhtml when the fixture's content is XHTML (all *-epub-type fixtures)
+    gnd.json               the expected Guided Navigation document produced from the input file
+    utterances.json        the expected utterance lists produced from gnd.json, forked by
+                            extraction format (plain/ssml), each with a baseline plus any
+                            option variants this fixture illustrates — see "Utterance
+                            extraction options" below
 ```
 
 `manifest.json` and `ROLES_COVERAGE.md` are both generated from the
@@ -76,29 +78,64 @@ Each fixture directory is fully self-contained and independently loadable.
   "role": "footnote",                     // the roles.md role name this fixture targets
   "rolesCovered": ["footnote", "noteref"],// every role name this fixture's markup exercises
   "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
-  "inputKind": "document",                // "fragment" | "document"
-  "skip": ["footnote"]                    // optional — see "Skippable roles" below
+  "inputKind": "document"                 // "fragment" | "document"
 }
 ```
 
-## Skippable roles
+## Utterance extraction options
 
-[roles.md#list-of-skippable-roles](https://github.com/readium/guided-navigation/blob/main/roles.md#list-of-skippable-roles)
-documents roles a *reader* may choose to skip past during playback (asides,
-footnotes, pagebreaks, tables of contents...) — they aren't omitted from
-utterance extraction by default, since every fixture's `utterances.json` is
-the unfiltered baseline. Skipping is instead a filter a consumer opts into
-at extraction time, given a set of roles to omit.
+Stage 2 (GND → utterances) takes options controlling *how* a fixed GND tree
+is turned into utterances — the tree itself never changes shape based on
+these; only the resulting utterance list does. `format` (`"plain"` or
+`"ssml"`) is required on every extraction, so `utterances.json` is forked
+into two top-level branches, `plain` and `ssml`, each holding:
 
-A fixture that exercises a skippable role may set `meta.json`'s optional
-`skip` field to the role(s) to test skipping for, and ship a sibling
-`utterances-skipped.json`: the exact `utterances.json` output, minus every
-node (and its whole subtree) whose role is in `skip`. Consuming this is the
-same as the base utterance check (see below), just with the role filter
-applied and compared against this file instead.
+```jsonc
+{
+  "plain": {
+    "base": [ /* the plain extraction with no other options */ ],
+    "variants": [
+      {
+        "options": { "skip": ["footnote"] },
+        "utterances": [ /* extraction with these options, plain format */ ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [ /* the ssml extraction with no other options */ ],
+    "variants": [ /* same options, ssml format */ ]
+  }
+}
+```
 
-Not every fixture needs this — only ones where skipping is illustrative
-(a footnote reached via noteref, a whole aside, a pagebreak announcement).
+`variants` entries never repeat `format` inside their own `options` — it's
+implied by which branch they live under. The other extraction options are:
+
+- `skip: GndRole[]` — omit a role (and its whole subtree) from the output,
+  e.g. so a reader can skip past footnotes or pagebreaks during playback.
+  See [roles.md#list-of-skippable-roles](https://github.com/readium/guided-navigation/blob/main/roles.md#list-of-skippable-roles)
+  for the roles.md-documented set a reader may choose to skip.
+- `contextualize: boolean` — whether synthesized announcements (pagebreak,
+  footnote start/end, and any role that gains one later) are spoken at all,
+  independent of the underlying content (which `skip` would instead omit
+  entirely). Default `true`.
+- `interruptSentence: boolean` — whether a pagebreak/footnote reference
+  that falls mid-sentence splits the sentence at that exact point, instead
+  of being spoken after the whole sentence finishes (the default).
+- `language: "never" | "block" | "inline"` — how a language shift between
+  adjacent text is rendered: dropped entirely, kept as separate
+  single-language utterances, or merged into one utterance with embedded
+  `<lang>` tags (`ssml` format only).
+
+Each `variants` entry is illustrative, not exhaustive — a fixture ships one
+only when that option actually changes its output, the same "not every
+fixture needs this" principle as fixture granularity in general (a
+footnote reached via noteref, a whole aside, a pagebreak announcement,
+...). Every fixture that ships an announcement-bearing base output should
+also illustrate `contextualize: false` — this isn't limited to today's
+`pagebreak`/`footnote`, since the announcement catalog is expected to grow
+to cover much of roles.md's structural vocabulary (chapters, headings,
+parts, credits, navigational lists...) over time.
 
 ## `epub:type` fixtures are full XHTML documents
 
@@ -107,7 +144,7 @@ the document root — it is **not** a plain-HTML attribute, and there is no
 "parse it as a literal attribute name in an HTML5 document" fallback: real
 EPUB reading systems parse content documents as namespace-aware XHTML. Every
 `*-epub-type` fixture therefore has `inputKind: "document"` and its
-`input.html` is a complete document:
+`input.xhtml` is a complete document:
 
 ```xml
 <?xml version="1.0" encoding="UTF-8"?>
@@ -149,44 +186,55 @@ A flat JSON array, one entry per fixture:
     "dir": "footnote-epub-type",
     "role": "footnote",
     "description": "Footnote encoded via epub:type, referenced by a noteref",
-    "skip": ["footnote"],
     "files": {
-      "input": "input.html",
+      "input": "input.xhtml",
       "gnd": "gnd.json",
-      "utterances": "utterances.json",
-      "utterancesSkipped": "utterances-skipped.json"
+      "utterances": "utterances.json"
     }
   }
 ]
 ```
 
-`skip` and `files.utterancesSkipped` are only present on fixtures that ship
-`utterances-skipped.json`.
-
 Any test runner, in any language, reads this one file to discover every
 fixture and resolve its file paths — no directory listing required.
 
 ## Consuming a fixture (any platform)
 
 1. Read `manifest.json`, iterate its entries.
-2. For each entry, read `input.html` and run it through your implementation
-   of stage 1 (HTML → GND) — compare the result to `gnd.json`.
+2. For each entry, read `files.input` (`input.html` or `input.xhtml`) and run
+   it through your implementation of stage 1 (HTML → GND) — compare the
+   result to `gnd.json`.
 3. Run the resulting GND document through your implementation of stage 2
-   (GND → utterances) — compare the result to `utterances.json`.
-4. If the entry has a `skip` field, run stage 2 again with that role set
-   passed as your implementation's skip filter — compare the result to
-   `utterances-skipped.json`.
+   (GND → utterances) twice, once with `{ format: "plain" }` and once with
+   `{ format: "ssml" }` — compare each to `utterances.json`'s corresponding
+   `plain.base`/`ssml.base`.
+4. For each entry in a branch's `variants` (if any), run stage 2 again with
+   that branch's format plus the variant's `options` — compare the result
+   to that variant's `utterances`.
 5. A fixture "passes" when every comparison it has files for matches exactly.
 
 ## Adding a new fixture
 
-1. `mkdir fixtures/<id>` and hand-write `input.html` for the specific
-   markup being tested.
-2. Hand-author `gnd.json` and `utterances.json` — there is no generator for
-   these; they are the ground truth implementations must match.
-3. If the fixture is illustrative for skipping (see "Skippable roles"
-   above), also hand-author `utterances-skipped.json` and set `meta.json`'s
-   `skip` field.
+1. `mkdir fixtures/<id>` and hand-write `input.html` (or `input.xhtml` for an
+   `epub:type` fixture, since `epub:type` requires XHTML — see above) for the
+   specific markup being tested.
+2. Hand-author `gnd.json` — there is no generator for it; it is the ground
+   truth implementations must match. This step still requires the same
+   scrutiny it always has: nothing here derives `gnd.json` from the input
+   file for you.
+3. Run `npm run generate-utterances` to derive `utterances.json` (both
+   format branches' `base`, plus whichever `variants` apply — see
+   "Utterance extraction options" above) from the `gnd.json` you just wrote,
+   using this package's own `extractUtterances()`. **Review the diff before
+   committing it** — `utterances.json` is still the ground truth other,
+   non-TypeScript implementations are meant to match, so generating it from
+   this repo's own implementation doesn't replace checking that what it
+   produced is actually correct for every option combination shown. This
+   also means: whenever `extractUtterances.ts`, `announcements.ts`, or
+   `skippableRoles` changes (a reworded announcement, a newly
+   contextualized role, a new skippable role), rerun this for every
+   affected fixture — hand-editing `utterances.json` to patch around a
+   wording change invites exactly the drift this script exists to prevent.
 4. Write `meta.json`.
 5. Run `npm run generate-fixtures-manifest` to regenerate `manifest.json`
    and `ROLES_COVERAGE.md` from what's now on disk.
diff --git a/fixtures/abstract-epub-type/gnd.json b/fixtures/abstract-epub-type/gnd.json
index feb99f1..e42be97 100644
--- a/fixtures/abstract-epub-type/gnd.json
+++ b/fixtures/abstract-epub-type/gnd.json
@@ -1,6 +1,13 @@
 {
   "role": [
-    "abstract"
+    "body"
   ],
-  "text": "This work examines the maintenance of coastal lighthouses in the 19th century."
+  "children": [
+    {
+      "text": "This work examines the maintenance of coastal lighthouses in the 19th century.",
+      "role": [
+        "abstract"
+      ]
+    }
+  ]
 }
diff --git a/fixtures/abstract-epub-type/input.html b/fixtures/abstract-epub-type/input.xhtml
similarity index 100%
rename from fixtures/abstract-epub-type/input.html
rename to fixtures/abstract-epub-type/input.xhtml
diff --git a/fixtures/abstract-epub-type/utterances.json b/fixtures/abstract-epub-type/utterances.json
index e98f268..b24da76 100644
--- a/fixtures/abstract-epub-type/utterances.json
+++ b/fixtures/abstract-epub-type/utterances.json
@@ -1,5 +1,46 @@
-[
-  {
-    "plain": "This work examines the maintenance of coastal lighthouses in the 19th century."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Abstract."
+      },
+      {
+        "plain": "This work examines the maintenance of coastal lighthouses in the 19th century."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "This work examines the maintenance of coastal lighthouses in the 19th century."
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Abstract."
+      },
+      {
+        "ssml": "This work examines the maintenance of coastal lighthouses in the 19th century."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "This work examines the maintenance of coastal lighthouses in the 19th century."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/abstract-role-aria/utterances.json b/fixtures/abstract-role-aria/utterances.json
index e98f268..b24da76 100644
--- a/fixtures/abstract-role-aria/utterances.json
+++ b/fixtures/abstract-role-aria/utterances.json
@@ -1,5 +1,46 @@
-[
-  {
-    "plain": "This work examines the maintenance of coastal lighthouses in the 19th century."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Abstract."
+      },
+      {
+        "plain": "This work examines the maintenance of coastal lighthouses in the 19th century."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "This work examines the maintenance of coastal lighthouses in the 19th century."
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Abstract."
+      },
+      {
+        "ssml": "This work examines the maintenance of coastal lighthouses in the 19th century."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "This work examines the maintenance of coastal lighthouses in the 19th century."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/acknowledgments-epub-type/gnd.json b/fixtures/acknowledgments-epub-type/gnd.json
index 9d8600b..01d3ced 100644
--- a/fixtures/acknowledgments-epub-type/gnd.json
+++ b/fixtures/acknowledgments-epub-type/gnd.json
@@ -1,6 +1,13 @@
 {
   "role": [
-    "acknowledgments"
+    "body"
   ],
-  "text": "The author thanks the keepers of Fastnet Rock for their recollections."
+  "children": [
+    {
+      "text": "The author thanks the keepers of Fastnet Rock for their recollections.",
+      "role": [
+        "acknowledgments"
+      ]
+    }
+  ]
 }
diff --git a/fixtures/acknowledgments-epub-type/input.html b/fixtures/acknowledgments-epub-type/input.xhtml
similarity index 100%
rename from fixtures/acknowledgments-epub-type/input.html
rename to fixtures/acknowledgments-epub-type/input.xhtml
diff --git a/fixtures/acknowledgments-epub-type/utterances.json b/fixtures/acknowledgments-epub-type/utterances.json
index ded247f..7253f7d 100644
--- a/fixtures/acknowledgments-epub-type/utterances.json
+++ b/fixtures/acknowledgments-epub-type/utterances.json
@@ -1,5 +1,52 @@
-[
-  {
-    "plain": "The author thanks the keepers of Fastnet Rock for their recollections."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the acknowledgments."
+      },
+      {
+        "plain": "The author thanks the keepers of Fastnet Rock for their recollections."
+      },
+      {
+        "plain": "End of the acknowledgments."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "The author thanks the keepers of Fastnet Rock for their recollections."
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the acknowledgments."
+      },
+      {
+        "ssml": "The author thanks the keepers of Fastnet Rock for their recollections."
+      },
+      {
+        "ssml": "End of the acknowledgments."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "The author thanks the keepers of Fastnet Rock for their recollections."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/acknowledgments-role-aria/utterances.json b/fixtures/acknowledgments-role-aria/utterances.json
index ded247f..7253f7d 100644
--- a/fixtures/acknowledgments-role-aria/utterances.json
+++ b/fixtures/acknowledgments-role-aria/utterances.json
@@ -1,5 +1,52 @@
-[
-  {
-    "plain": "The author thanks the keepers of Fastnet Rock for their recollections."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the acknowledgments."
+      },
+      {
+        "plain": "The author thanks the keepers of Fastnet Rock for their recollections."
+      },
+      {
+        "plain": "End of the acknowledgments."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "The author thanks the keepers of Fastnet Rock for their recollections."
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the acknowledgments."
+      },
+      {
+        "ssml": "The author thanks the keepers of Fastnet Rock for their recollections."
+      },
+      {
+        "ssml": "End of the acknowledgments."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "The author thanks the keepers of Fastnet Rock for their recollections."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/afterword-epub-type/gnd.json b/fixtures/afterword-epub-type/gnd.json
index 9757a46..6e2d047 100644
--- a/fixtures/afterword-epub-type/gnd.json
+++ b/fixtures/afterword-epub-type/gnd.json
@@ -1,6 +1,13 @@
 {
   "role": [
-    "afterword"
+    "body"
   ],
-  "text": "Years later, the last lighthouse keeper reflects on automation."
+  "children": [
+    {
+      "text": "Years later, the last lighthouse keeper reflects on automation.",
+      "role": [
+        "afterword"
+      ]
+    }
+  ]
 }
diff --git a/fixtures/afterword-epub-type/input.html b/fixtures/afterword-epub-type/input.xhtml
similarity index 100%
rename from fixtures/afterword-epub-type/input.html
rename to fixtures/afterword-epub-type/input.xhtml
diff --git a/fixtures/afterword-epub-type/utterances.json b/fixtures/afterword-epub-type/utterances.json
index fc9f423..6e0a7be 100644
--- a/fixtures/afterword-epub-type/utterances.json
+++ b/fixtures/afterword-epub-type/utterances.json
@@ -1,5 +1,52 @@
-[
-  {
-    "plain": "Years later, the last lighthouse keeper reflects on automation."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the afterword."
+      },
+      {
+        "plain": "Years later, the last lighthouse keeper reflects on automation."
+      },
+      {
+        "plain": "End of the afterword."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "Years later, the last lighthouse keeper reflects on automation."
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the afterword."
+      },
+      {
+        "ssml": "Years later, the last lighthouse keeper reflects on automation."
+      },
+      {
+        "ssml": "End of the afterword."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "Years later, the last lighthouse keeper reflects on automation."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/afterword-role-aria/utterances.json b/fixtures/afterword-role-aria/utterances.json
index fc9f423..6e0a7be 100644
--- a/fixtures/afterword-role-aria/utterances.json
+++ b/fixtures/afterword-role-aria/utterances.json
@@ -1,5 +1,52 @@
-[
-  {
-    "plain": "Years later, the last lighthouse keeper reflects on automation."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the afterword."
+      },
+      {
+        "plain": "Years later, the last lighthouse keeper reflects on automation."
+      },
+      {
+        "plain": "End of the afterword."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "Years later, the last lighthouse keeper reflects on automation."
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the afterword."
+      },
+      {
+        "ssml": "Years later, the last lighthouse keeper reflects on automation."
+      },
+      {
+        "ssml": "End of the afterword."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "Years later, the last lighthouse keeper reflects on automation."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/appendix-epub-type/gnd.json b/fixtures/appendix-epub-type/gnd.json
index a946bd6..f96e969 100644
--- a/fixtures/appendix-epub-type/gnd.json
+++ b/fixtures/appendix-epub-type/gnd.json
@@ -1,7 +1,14 @@
 {
   "role": [
-    "section",
-    "appendix"
+    "body"
   ],
-  "text": "A table of lighthouse construction dates referenced in the text."
+  "children": [
+    {
+      "text": "A table of lighthouse construction dates referenced in the text.",
+      "role": [
+        "section",
+        "appendix"
+      ]
+    }
+  ]
 }
diff --git a/fixtures/appendix-epub-type/input.html b/fixtures/appendix-epub-type/input.xhtml
similarity index 100%
rename from fixtures/appendix-epub-type/input.html
rename to fixtures/appendix-epub-type/input.xhtml
diff --git a/fixtures/appendix-epub-type/utterances.json b/fixtures/appendix-epub-type/utterances.json
index 514edbc..4f0a98d 100644
--- a/fixtures/appendix-epub-type/utterances.json
+++ b/fixtures/appendix-epub-type/utterances.json
@@ -1,5 +1,52 @@
-[
-  {
-    "plain": "A table of lighthouse construction dates referenced in the text."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the appendix."
+      },
+      {
+        "plain": "A table of lighthouse construction dates referenced in the text."
+      },
+      {
+        "plain": "End of the appendix."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "A table of lighthouse construction dates referenced in the text."
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the appendix."
+      },
+      {
+        "ssml": "A table of lighthouse construction dates referenced in the text."
+      },
+      {
+        "ssml": "End of the appendix."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "A table of lighthouse construction dates referenced in the text."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/appendix-role-aria/utterances.json b/fixtures/appendix-role-aria/utterances.json
index 514edbc..4f0a98d 100644
--- a/fixtures/appendix-role-aria/utterances.json
+++ b/fixtures/appendix-role-aria/utterances.json
@@ -1,5 +1,52 @@
-[
-  {
-    "plain": "A table of lighthouse construction dates referenced in the text."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the appendix."
+      },
+      {
+        "plain": "A table of lighthouse construction dates referenced in the text."
+      },
+      {
+        "plain": "End of the appendix."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "A table of lighthouse construction dates referenced in the text."
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the appendix."
+      },
+      {
+        "ssml": "A table of lighthouse construction dates referenced in the text."
+      },
+      {
+        "ssml": "End of the appendix."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "A table of lighthouse construction dates referenced in the text."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/article-html-native/utterances.json b/fixtures/article-html-native/utterances.json
index ad408d7..3999bea 100644
--- a/fixtures/article-html-native/utterances.json
+++ b/fixtures/article-html-native/utterances.json
@@ -1,5 +1,16 @@
-[
-  {
-    "plain": "A self-contained article about lighthouse keeping."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "A self-contained article about lighthouse keeping."
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "A self-contained article about lighthouse keeping."
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/aside-html-native/meta.json b/fixtures/aside-html-native/meta.json
index 117ff92..87272cc 100644
--- a/fixtures/aside-html-native/meta.json
+++ b/fixtures/aside-html-native/meta.json
@@ -6,6 +6,5 @@
     "aside"
   ],
   "sourceRef": "https://github.com/readium/guided-navigation/blob/main/roles.md",
-  "inputKind": "fragment",
-  "skip": ["aside"]
+  "inputKind": "fragment"
 }
diff --git a/fixtures/aside-html-native/utterances-skipped.json b/fixtures/aside-html-native/utterances-skipped.json
deleted file mode 100644
index fe51488..0000000
--- a/fixtures/aside-html-native/utterances-skipped.json
+++ /dev/null
@@ -1 +0,0 @@
-[]
diff --git a/fixtures/aside-html-native/utterances.json b/fixtures/aside-html-native/utterances.json
index 2daf50b..890b9c3 100644
--- a/fixtures/aside-html-native/utterances.json
+++ b/fixtures/aside-html-native/utterances.json
@@ -1,5 +1,68 @@
-[
-  {
-    "plain": "By the way, lighthouses were once staffed around the clock."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the aside."
+      },
+      {
+        "plain": "By the way, lighthouses were once staffed around the clock."
+      },
+      {
+        "plain": "End of the aside."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "skip": [
+            "aside"
+          ]
+        },
+        "utterances": []
+      },
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "By the way, lighthouses were once staffed around the clock."
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the aside."
+      },
+      {
+        "ssml": "By the way, lighthouses were once staffed around the clock."
+      },
+      {
+        "ssml": "End of the aside."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "skip": [
+            "aside"
+          ]
+        },
+        "utterances": []
+      },
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "By the way, lighthouses were once staffed around the clock."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/audio-html-native/utterances.json b/fixtures/audio-html-native/utterances.json
index 4b371cf..28a270b 100644
--- a/fixtures/audio-html-native/utterances.json
+++ b/fixtures/audio-html-native/utterances.json
@@ -1,5 +1,16 @@
-[
-  {
-    "plain": "Foghorn recording from the 1962 restoration"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Foghorn recording from the 1962 restoration"
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Foghorn recording from the 1962 restoration"
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/backlink-epub-type/gnd.json b/fixtures/backlink-epub-type/gnd.json
index d9653e3..0610f1c 100644
--- a/fixtures/backlink-epub-type/gnd.json
+++ b/fixtures/backlink-epub-type/gnd.json
@@ -1,7 +1,14 @@
 {
   "role": [
-    "backlink"
+    "body"
   ],
-  "text": "Return to reference",
-  "textref": "#ref1"
+  "children": [
+    {
+      "textref": "#ref1",
+      "text": "Return to reference",
+      "role": [
+        "backlink"
+      ]
+    }
+  ]
 }
diff --git a/fixtures/backlink-epub-type/input.html b/fixtures/backlink-epub-type/input.xhtml
similarity index 100%
rename from fixtures/backlink-epub-type/input.html
rename to fixtures/backlink-epub-type/input.xhtml
diff --git a/fixtures/backlink-epub-type/utterances.json b/fixtures/backlink-epub-type/utterances.json
index f32b425..611f690 100644
--- a/fixtures/backlink-epub-type/utterances.json
+++ b/fixtures/backlink-epub-type/utterances.json
@@ -1,5 +1,16 @@
-[
-  {
-    "plain": "Return to reference"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Return to reference"
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Return to reference"
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/backlink-role-aria/utterances.json b/fixtures/backlink-role-aria/utterances.json
index f32b425..611f690 100644
--- a/fixtures/backlink-role-aria/utterances.json
+++ b/fixtures/backlink-role-aria/utterances.json
@@ -1,5 +1,16 @@
-[
-  {
-    "plain": "Return to reference"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Return to reference"
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Return to reference"
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/bibliography-epub-type/gnd.json b/fixtures/bibliography-epub-type/gnd.json
index 91f4f6a..0e3da34 100644
--- a/fixtures/bibliography-epub-type/gnd.json
+++ b/fixtures/bibliography-epub-type/gnd.json
@@ -1,25 +1,32 @@
 {
   "role": [
-    "section",
-    "bibliography"
+    "body"
   ],
   "children": [
     {
       "role": [
-        "list"
+        "section",
+        "bibliography"
       ],
       "children": [
         {
           "role": [
-            "listItem"
+            "list"
           ],
-          "text": "Smith, J. Lighthouses of the Atlantic. 1988."
-        },
-        {
-          "role": [
-            "listItem"
-          ],
-          "text": "Doe, A. Coastal Illumination. 1975."
+          "children": [
+            {
+              "text": "Smith, J. Lighthouses of the Atlantic. 1988.",
+              "role": [
+                "listItem"
+              ]
+            },
+            {
+              "text": "Doe, A. Coastal Illumination. 1975.",
+              "role": [
+                "listItem"
+              ]
+            }
+          ]
         }
       ]
     }
diff --git a/fixtures/bibliography-epub-type/input.html b/fixtures/bibliography-epub-type/input.xhtml
similarity index 100%
rename from fixtures/bibliography-epub-type/input.html
rename to fixtures/bibliography-epub-type/input.xhtml
diff --git a/fixtures/bibliography-epub-type/utterances.json b/fixtures/bibliography-epub-type/utterances.json
index c1bf5a3..e6dee95 100644
--- a/fixtures/bibliography-epub-type/utterances.json
+++ b/fixtures/bibliography-epub-type/utterances.json
@@ -1,8 +1,80 @@
-[
-  {
-    "plain": "Smith, J. Lighthouses of the Atlantic. 1988."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the bibliography."
+      },
+      {
+        "plain": "Smith, J. Lighthouses of the Atlantic. 1988."
+      },
+      {
+        "plain": "Doe, A. Coastal Illumination. 1975."
+      },
+      {
+        "plain": "End of the bibliography."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "skip": [
+            "bibliography"
+          ]
+        },
+        "utterances": []
+      },
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "Smith, J. Lighthouses of the Atlantic. 1988."
+          },
+          {
+            "plain": "Doe, A. Coastal Illumination. 1975."
+          }
+        ]
+      }
+    ]
   },
-  {
-    "plain": "Doe, A. Coastal Illumination. 1975."
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the bibliography."
+      },
+      {
+        "ssml": "Smith, J. Lighthouses of the Atlantic. 1988."
+      },
+      {
+        "ssml": "Doe, A. Coastal Illumination. 1975."
+      },
+      {
+        "ssml": "End of the bibliography."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "skip": [
+            "bibliography"
+          ]
+        },
+        "utterances": []
+      },
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "Smith, J. Lighthouses of the Atlantic. 1988."
+          },
+          {
+            "ssml": "Doe, A. Coastal Illumination. 1975."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/bibliography-role-aria/utterances.json b/fixtures/bibliography-role-aria/utterances.json
index c1bf5a3..e6dee95 100644
--- a/fixtures/bibliography-role-aria/utterances.json
+++ b/fixtures/bibliography-role-aria/utterances.json
@@ -1,8 +1,80 @@
-[
-  {
-    "plain": "Smith, J. Lighthouses of the Atlantic. 1988."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the bibliography."
+      },
+      {
+        "plain": "Smith, J. Lighthouses of the Atlantic. 1988."
+      },
+      {
+        "plain": "Doe, A. Coastal Illumination. 1975."
+      },
+      {
+        "plain": "End of the bibliography."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "skip": [
+            "bibliography"
+          ]
+        },
+        "utterances": []
+      },
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "Smith, J. Lighthouses of the Atlantic. 1988."
+          },
+          {
+            "plain": "Doe, A. Coastal Illumination. 1975."
+          }
+        ]
+      }
+    ]
   },
-  {
-    "plain": "Doe, A. Coastal Illumination. 1975."
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the bibliography."
+      },
+      {
+        "ssml": "Smith, J. Lighthouses of the Atlantic. 1988."
+      },
+      {
+        "ssml": "Doe, A. Coastal Illumination. 1975."
+      },
+      {
+        "ssml": "End of the bibliography."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "skip": [
+            "bibliography"
+          ]
+        },
+        "utterances": []
+      },
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "Smith, J. Lighthouses of the Atlantic. 1988."
+          },
+          {
+            "ssml": "Doe, A. Coastal Illumination. 1975."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/biblioref-epub-type/gnd.json b/fixtures/biblioref-epub-type/gnd.json
index b0a664f..5f120fe 100644
--- a/fixtures/biblioref-epub-type/gnd.json
+++ b/fixtures/biblioref-epub-type/gnd.json
@@ -1,7 +1,14 @@
 {
   "role": [
-    "biblioref"
+    "body"
   ],
-  "text": "See Smith, 1988",
-  "textref": "#smith1988"
+  "children": [
+    {
+      "textref": "#smith1988",
+      "text": "See Smith, 1988",
+      "role": [
+        "biblioref"
+      ]
+    }
+  ]
 }
diff --git a/fixtures/biblioref-epub-type/input.html b/fixtures/biblioref-epub-type/input.xhtml
similarity index 100%
rename from fixtures/biblioref-epub-type/input.html
rename to fixtures/biblioref-epub-type/input.xhtml
diff --git a/fixtures/biblioref-epub-type/utterances.json b/fixtures/biblioref-epub-type/utterances.json
index 8740d24..f5fad12 100644
--- a/fixtures/biblioref-epub-type/utterances.json
+++ b/fixtures/biblioref-epub-type/utterances.json
@@ -1,5 +1,16 @@
-[
-  {
-    "plain": "See Smith, 1988"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "See Smith, 1988"
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "See Smith, 1988"
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/biblioref-role-aria/utterances.json b/fixtures/biblioref-role-aria/utterances.json
index 8740d24..f5fad12 100644
--- a/fixtures/biblioref-role-aria/utterances.json
+++ b/fixtures/biblioref-role-aria/utterances.json
@@ -1,5 +1,16 @@
-[
-  {
-    "plain": "See Smith, 1988"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "See Smith, 1988"
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "See Smith, 1988"
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/blockquote-html-native/utterances.json b/fixtures/blockquote-html-native/utterances.json
index 98227d2..30dc249 100644
--- a/fixtures/blockquote-html-native/utterances.json
+++ b/fixtures/blockquote-html-native/utterances.json
@@ -1,5 +1,16 @@
-[
-  {
-    "plain": "To be, or not to be, that is the question."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "To be, or not to be, that is the question."
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "To be, or not to be, that is the question."
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/body-html-native/utterances.json b/fixtures/body-html-native/utterances.json
index 6138e6f..167622d 100644
--- a/fixtures/body-html-native/utterances.json
+++ b/fixtures/body-html-native/utterances.json
@@ -1,5 +1,16 @@
-[
-  {
-    "plain": "The full content of the document."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "The full content of the document."
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "The full content of the document."
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/chapter-epub-type/gnd.json b/fixtures/chapter-epub-type/gnd.json
index 137ad53..8a068e2 100644
--- a/fixtures/chapter-epub-type/gnd.json
+++ b/fixtures/chapter-epub-type/gnd.json
@@ -1,14 +1,21 @@
 {
   "role": [
-    "section",
-    "chapter"
+    "body"
   ],
   "children": [
     {
       "role": [
-        "heading1"
+        "section",
+        "chapter"
       ],
-      "text": "Title of the chapter"
+      "children": [
+        {
+          "text": "Title of the chapter",
+          "role": [
+            "heading1"
+          ]
+        }
+      ]
     }
   ]
 }
diff --git a/fixtures/chapter-epub-type/input.html b/fixtures/chapter-epub-type/input.xhtml
similarity index 100%
rename from fixtures/chapter-epub-type/input.html
rename to fixtures/chapter-epub-type/input.xhtml
diff --git a/fixtures/chapter-epub-type/utterances.json b/fixtures/chapter-epub-type/utterances.json
index 55f8470..d995165 100644
--- a/fixtures/chapter-epub-type/utterances.json
+++ b/fixtures/chapter-epub-type/utterances.json
@@ -1,5 +1,58 @@
-[
-  {
-    "plain": "Title of the chapter"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the chapter."
+      },
+      {
+        "plain": "Heading level 1."
+      },
+      {
+        "plain": "Title of the chapter"
+      },
+      {
+        "plain": "End of the chapter."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "Title of the chapter"
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the chapter."
+      },
+      {
+        "ssml": "Heading level 1."
+      },
+      {
+        "ssml": "Title of the chapter"
+      },
+      {
+        "ssml": "End of the chapter."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "Title of the chapter"
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/chapter-role-aria/utterances.json b/fixtures/chapter-role-aria/utterances.json
index 55f8470..d995165 100644
--- a/fixtures/chapter-role-aria/utterances.json
+++ b/fixtures/chapter-role-aria/utterances.json
@@ -1,5 +1,58 @@
-[
-  {
-    "plain": "Title of the chapter"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the chapter."
+      },
+      {
+        "plain": "Heading level 1."
+      },
+      {
+        "plain": "Title of the chapter"
+      },
+      {
+        "plain": "End of the chapter."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "Title of the chapter"
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the chapter."
+      },
+      {
+        "ssml": "Heading level 1."
+      },
+      {
+        "ssml": "Title of the chapter"
+      },
+      {
+        "ssml": "End of the chapter."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "Title of the chapter"
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/colophon-epub-type/gnd.json b/fixtures/colophon-epub-type/gnd.json
index 9cc935c..f0561ee 100644
--- a/fixtures/colophon-epub-type/gnd.json
+++ b/fixtures/colophon-epub-type/gnd.json
@@ -1,6 +1,13 @@
 {
   "role": [
-    "colophon"
+    "body"
   ],
-  "text": "Set in Georgia, 11pt, on recycled paper."
+  "children": [
+    {
+      "text": "Set in Georgia, 11pt, on recycled paper.",
+      "role": [
+        "colophon"
+      ]
+    }
+  ]
 }
diff --git a/fixtures/colophon-epub-type/input.html b/fixtures/colophon-epub-type/input.xhtml
similarity index 100%
rename from fixtures/colophon-epub-type/input.html
rename to fixtures/colophon-epub-type/input.xhtml
diff --git a/fixtures/colophon-epub-type/utterances.json b/fixtures/colophon-epub-type/utterances.json
index 0232ee1..8f02e41 100644
--- a/fixtures/colophon-epub-type/utterances.json
+++ b/fixtures/colophon-epub-type/utterances.json
@@ -1,5 +1,46 @@
-[
-  {
-    "plain": "Set in Georgia, 11pt, on recycled paper."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Colophon."
+      },
+      {
+        "plain": "Set in Georgia, 11pt, on recycled paper."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "Set in Georgia, 11pt, on recycled paper."
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Colophon."
+      },
+      {
+        "ssml": "Set in Georgia, 11pt, on recycled paper."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "Set in Georgia, 11pt, on recycled paper."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/colophon-role-aria/utterances.json b/fixtures/colophon-role-aria/utterances.json
index 0232ee1..8f02e41 100644
--- a/fixtures/colophon-role-aria/utterances.json
+++ b/fixtures/colophon-role-aria/utterances.json
@@ -1,5 +1,46 @@
-[
-  {
-    "plain": "Set in Georgia, 11pt, on recycled paper."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Colophon."
+      },
+      {
+        "plain": "Set in Georgia, 11pt, on recycled paper."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "Set in Georgia, 11pt, on recycled paper."
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Colophon."
+      },
+      {
+        "ssml": "Set in Georgia, 11pt, on recycled paper."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "Set in Georgia, 11pt, on recycled paper."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/complementary-role-aria/utterances.json b/fixtures/complementary-role-aria/utterances.json
index 66e157d..81286c8 100644
--- a/fixtures/complementary-role-aria/utterances.json
+++ b/fixtures/complementary-role-aria/utterances.json
@@ -1,5 +1,16 @@
-[
-  {
-    "plain": "A supporting note related to the main content."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "A supporting note related to the main content."
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "A supporting note related to the main content."
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/conclusion-epub-type/gnd.json b/fixtures/conclusion-epub-type/gnd.json
index 69ea621..65a0127 100644
--- a/fixtures/conclusion-epub-type/gnd.json
+++ b/fixtures/conclusion-epub-type/gnd.json
@@ -1,6 +1,13 @@
 {
   "role": [
-    "conclusion"
+    "body"
   ],
-  "text": "Lighthouses remain a symbol of safe passage."
+  "children": [
+    {
+      "text": "Lighthouses remain a symbol of safe passage.",
+      "role": [
+        "conclusion"
+      ]
+    }
+  ]
 }
diff --git a/fixtures/conclusion-epub-type/input.html b/fixtures/conclusion-epub-type/input.xhtml
similarity index 100%
rename from fixtures/conclusion-epub-type/input.html
rename to fixtures/conclusion-epub-type/input.xhtml
diff --git a/fixtures/conclusion-epub-type/utterances.json b/fixtures/conclusion-epub-type/utterances.json
index da383c0..234fa8c 100644
--- a/fixtures/conclusion-epub-type/utterances.json
+++ b/fixtures/conclusion-epub-type/utterances.json
@@ -1,5 +1,52 @@
-[
-  {
-    "plain": "Lighthouses remain a symbol of safe passage."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the conclusion."
+      },
+      {
+        "plain": "Lighthouses remain a symbol of safe passage."
+      },
+      {
+        "plain": "End of the conclusion."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "Lighthouses remain a symbol of safe passage."
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the conclusion."
+      },
+      {
+        "ssml": "Lighthouses remain a symbol of safe passage."
+      },
+      {
+        "ssml": "End of the conclusion."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "Lighthouses remain a symbol of safe passage."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/conclusion-role-aria/utterances.json b/fixtures/conclusion-role-aria/utterances.json
index da383c0..234fa8c 100644
--- a/fixtures/conclusion-role-aria/utterances.json
+++ b/fixtures/conclusion-role-aria/utterances.json
@@ -1,5 +1,52 @@
-[
-  {
-    "plain": "Lighthouses remain a symbol of safe passage."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the conclusion."
+      },
+      {
+        "plain": "Lighthouses remain a symbol of safe passage."
+      },
+      {
+        "plain": "End of the conclusion."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "Lighthouses remain a symbol of safe passage."
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the conclusion."
+      },
+      {
+        "ssml": "Lighthouses remain a symbol of safe passage."
+      },
+      {
+        "ssml": "End of the conclusion."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "Lighthouses remain a symbol of safe passage."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/cover-epub-type/gnd.json b/fixtures/cover-epub-type/gnd.json
index 76a839b..42866e5 100644
--- a/fixtures/cover-epub-type/gnd.json
+++ b/fixtures/cover-epub-type/gnd.json
@@ -1,15 +1,22 @@
 {
   "role": [
-    "section",
-    "cover"
+    "body"
   ],
   "children": [
     {
       "role": [
-        "image"
+        "section",
+        "cover"
       ],
-      "imgref": "cover.jpg",
-      "description": "Lighthouses of the Atlantic, by J. Smith"
+      "children": [
+        {
+          "imgref": "cover.jpg",
+          "role": [
+            "image"
+          ],
+          "description": "Lighthouses of the Atlantic, by J. Smith"
+        }
+      ]
     }
   ]
 }
diff --git a/fixtures/cover-epub-type/input.html b/fixtures/cover-epub-type/input.xhtml
similarity index 100%
rename from fixtures/cover-epub-type/input.html
rename to fixtures/cover-epub-type/input.xhtml
diff --git a/fixtures/cover-epub-type/utterances.json b/fixtures/cover-epub-type/utterances.json
index 01408d7..b1c673f 100644
--- a/fixtures/cover-epub-type/utterances.json
+++ b/fixtures/cover-epub-type/utterances.json
@@ -1,5 +1,46 @@
-[
-  {
-    "plain": "Lighthouses of the Atlantic, by J. Smith"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Cover."
+      },
+      {
+        "plain": "Lighthouses of the Atlantic, by J. Smith"
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "Lighthouses of the Atlantic, by J. Smith"
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Cover."
+      },
+      {
+        "ssml": "Lighthouses of the Atlantic, by J. Smith"
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "Lighthouses of the Atlantic, by J. Smith"
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/cover-role-aria/utterances.json b/fixtures/cover-role-aria/utterances.json
index 01408d7..b1c673f 100644
--- a/fixtures/cover-role-aria/utterances.json
+++ b/fixtures/cover-role-aria/utterances.json
@@ -1,5 +1,46 @@
-[
-  {
-    "plain": "Lighthouses of the Atlantic, by J. Smith"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Cover."
+      },
+      {
+        "plain": "Lighthouses of the Atlantic, by J. Smith"
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "Lighthouses of the Atlantic, by J. Smith"
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Cover."
+      },
+      {
+        "ssml": "Lighthouses of the Atlantic, by J. Smith"
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "Lighthouses of the Atlantic, by J. Smith"
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/credit-epub-type/gnd.json b/fixtures/credit-epub-type/gnd.json
index fb429cb..640d0b1 100644
--- a/fixtures/credit-epub-type/gnd.json
+++ b/fixtures/credit-epub-type/gnd.json
@@ -1,13 +1,20 @@
 {
   "role": [
-    "paragraph"
+    "body"
   ],
   "children": [
     {
       "role": [
-        "credit"
+        "paragraph"
       ],
-      "text": "Cover photograph by A. Keeper."
+      "children": [
+        {
+          "text": "Cover photograph by A. Keeper.",
+          "role": [
+            "credit"
+          ]
+        }
+      ]
     }
   ]
 }
diff --git a/fixtures/credit-epub-type/input.html b/fixtures/credit-epub-type/input.xhtml
similarity index 100%
rename from fixtures/credit-epub-type/input.html
rename to fixtures/credit-epub-type/input.xhtml
diff --git a/fixtures/credit-epub-type/utterances.json b/fixtures/credit-epub-type/utterances.json
index ea556e4..54c5fef 100644
--- a/fixtures/credit-epub-type/utterances.json
+++ b/fixtures/credit-epub-type/utterances.json
@@ -1,5 +1,46 @@
-[
-  {
-    "plain": "Cover photograph by A. Keeper."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Credit."
+      },
+      {
+        "plain": "Cover photograph by A. Keeper."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "Cover photograph by A. Keeper."
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Credit."
+      },
+      {
+        "ssml": "Cover photograph by A. Keeper."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "Cover photograph by A. Keeper."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/credit-role-aria/utterances.json b/fixtures/credit-role-aria/utterances.json
index ea556e4..54c5fef 100644
--- a/fixtures/credit-role-aria/utterances.json
+++ b/fixtures/credit-role-aria/utterances.json
@@ -1,5 +1,46 @@
-[
-  {
-    "plain": "Cover photograph by A. Keeper."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Credit."
+      },
+      {
+        "plain": "Cover photograph by A. Keeper."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "Cover photograph by A. Keeper."
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Credit."
+      },
+      {
+        "ssml": "Cover photograph by A. Keeper."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "Cover photograph by A. Keeper."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/credits-epub-type/gnd.json b/fixtures/credits-epub-type/gnd.json
index b4d5979..fc29aae 100644
--- a/fixtures/credits-epub-type/gnd.json
+++ b/fixtures/credits-epub-type/gnd.json
@@ -1,36 +1,43 @@
 {
   "role": [
-    "credits"
+    "body"
   ],
   "children": [
     {
       "role": [
-        "list"
+        "credits"
       ],
       "children": [
         {
           "role": [
-            "listItem"
+            "list"
           ],
           "children": [
             {
               "role": [
-                "credit"
+                "listItem"
               ],
-              "text": "Cover photograph by A. Keeper."
-            }
-          ]
-        },
-        {
-          "role": [
-            "listItem"
-          ],
-          "children": [
+              "children": [
+                {
+                  "text": "Cover photograph by A. Keeper.",
+                  "role": [
+                    "credit"
+                  ]
+                }
+              ]
+            },
             {
               "role": [
-                "credit"
+                "listItem"
               ],
-              "text": "Maps by B. Cartographer."
+              "children": [
+                {
+                  "text": "Maps by B. Cartographer.",
+                  "role": [
+                    "credit"
+                  ]
+                }
+              ]
             }
           ]
         }
diff --git a/fixtures/credits-epub-type/input.html b/fixtures/credits-epub-type/input.xhtml
similarity index 100%
rename from fixtures/credits-epub-type/input.html
rename to fixtures/credits-epub-type/input.xhtml
diff --git a/fixtures/credits-epub-type/utterances.json b/fixtures/credits-epub-type/utterances.json
index 987e8cb..56591df 100644
--- a/fixtures/credits-epub-type/utterances.json
+++ b/fixtures/credits-epub-type/utterances.json
@@ -1,8 +1,76 @@
-[
-  {
-    "plain": "Cover photograph by A. Keeper."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the credits."
+      },
+      {
+        "plain": "Credit."
+      },
+      {
+        "plain": "Cover photograph by A. Keeper."
+      },
+      {
+        "plain": "Credit."
+      },
+      {
+        "plain": "Maps by B. Cartographer."
+      },
+      {
+        "plain": "End of the credits."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "Cover photograph by A. Keeper."
+          },
+          {
+            "plain": "Maps by B. Cartographer."
+          }
+        ]
+      }
+    ]
   },
-  {
-    "plain": "Maps by B. Cartographer."
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the credits."
+      },
+      {
+        "ssml": "Credit."
+      },
+      {
+        "ssml": "Cover photograph by A. Keeper."
+      },
+      {
+        "ssml": "Credit."
+      },
+      {
+        "ssml": "Maps by B. Cartographer."
+      },
+      {
+        "ssml": "End of the credits."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "Cover photograph by A. Keeper."
+          },
+          {
+            "ssml": "Maps by B. Cartographer."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/credits-role-aria/utterances.json b/fixtures/credits-role-aria/utterances.json
index 987e8cb..56591df 100644
--- a/fixtures/credits-role-aria/utterances.json
+++ b/fixtures/credits-role-aria/utterances.json
@@ -1,8 +1,76 @@
-[
-  {
-    "plain": "Cover photograph by A. Keeper."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the credits."
+      },
+      {
+        "plain": "Credit."
+      },
+      {
+        "plain": "Cover photograph by A. Keeper."
+      },
+      {
+        "plain": "Credit."
+      },
+      {
+        "plain": "Maps by B. Cartographer."
+      },
+      {
+        "plain": "End of the credits."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "Cover photograph by A. Keeper."
+          },
+          {
+            "plain": "Maps by B. Cartographer."
+          }
+        ]
+      }
+    ]
   },
-  {
-    "plain": "Maps by B. Cartographer."
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the credits."
+      },
+      {
+        "ssml": "Credit."
+      },
+      {
+        "ssml": "Cover photograph by A. Keeper."
+      },
+      {
+        "ssml": "Credit."
+      },
+      {
+        "ssml": "Maps by B. Cartographer."
+      },
+      {
+        "ssml": "End of the credits."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "Cover photograph by A. Keeper."
+          },
+          {
+            "ssml": "Maps by B. Cartographer."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/dedication-epub-type/gnd.json b/fixtures/dedication-epub-type/gnd.json
index 22cc2b2..87ccde1 100644
--- a/fixtures/dedication-epub-type/gnd.json
+++ b/fixtures/dedication-epub-type/gnd.json
@@ -1,6 +1,13 @@
 {
   "role": [
-    "dedication"
+    "body"
   ],
-  "text": "For every keeper who lit the lamp at dusk."
+  "children": [
+    {
+      "text": "For every keeper who lit the lamp at dusk.",
+      "role": [
+        "dedication"
+      ]
+    }
+  ]
 }
diff --git a/fixtures/dedication-epub-type/input.html b/fixtures/dedication-epub-type/input.xhtml
similarity index 100%
rename from fixtures/dedication-epub-type/input.html
rename to fixtures/dedication-epub-type/input.xhtml
diff --git a/fixtures/dedication-epub-type/utterances.json b/fixtures/dedication-epub-type/utterances.json
index 12e1744..e504a79 100644
--- a/fixtures/dedication-epub-type/utterances.json
+++ b/fixtures/dedication-epub-type/utterances.json
@@ -1,5 +1,46 @@
-[
-  {
-    "plain": "For every keeper who lit the lamp at dusk."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Dedication."
+      },
+      {
+        "plain": "For every keeper who lit the lamp at dusk."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "For every keeper who lit the lamp at dusk."
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Dedication."
+      },
+      {
+        "ssml": "For every keeper who lit the lamp at dusk."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "For every keeper who lit the lamp at dusk."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/dedication-role-aria/utterances.json b/fixtures/dedication-role-aria/utterances.json
index 12e1744..e504a79 100644
--- a/fixtures/dedication-role-aria/utterances.json
+++ b/fixtures/dedication-role-aria/utterances.json
@@ -1,5 +1,46 @@
-[
-  {
-    "plain": "For every keeper who lit the lamp at dusk."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Dedication."
+      },
+      {
+        "plain": "For every keeper who lit the lamp at dusk."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "For every keeper who lit the lamp at dusk."
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Dedication."
+      },
+      {
+        "ssml": "For every keeper who lit the lamp at dusk."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "For every keeper who lit the lamp at dusk."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/definition-epub-type/gnd.json b/fixtures/definition-epub-type/gnd.json
index 27ad288..c679eee 100644
--- a/fixtures/definition-epub-type/gnd.json
+++ b/fixtures/definition-epub-type/gnd.json
@@ -1,13 +1,20 @@
 {
   "role": [
-    "glossary"
+    "body"
   ],
   "children": [
     {
       "role": [
-        "definition"
+        "glossary"
       ],
-      "text": "A structure that contains an enumeration of related content items."
+      "children": [
+        {
+          "text": "A structure that contains an enumeration of related content items.",
+          "role": [
+            "definition"
+          ]
+        }
+      ]
     }
   ]
 }
diff --git a/fixtures/definition-epub-type/input.html b/fixtures/definition-epub-type/input.xhtml
similarity index 100%
rename from fixtures/definition-epub-type/input.html
rename to fixtures/definition-epub-type/input.xhtml
diff --git a/fixtures/definition-epub-type/utterances.json b/fixtures/definition-epub-type/utterances.json
index 269bed0..cb41f2a 100644
--- a/fixtures/definition-epub-type/utterances.json
+++ b/fixtures/definition-epub-type/utterances.json
@@ -1,5 +1,52 @@
-[
-  {
-    "plain": "A structure that contains an enumeration of related content items."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the glossary."
+      },
+      {
+        "plain": "A structure that contains an enumeration of related content items."
+      },
+      {
+        "plain": "End of the glossary."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "A structure that contains an enumeration of related content items."
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the glossary."
+      },
+      {
+        "ssml": "A structure that contains an enumeration of related content items."
+      },
+      {
+        "ssml": "End of the glossary."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "A structure that contains an enumeration of related content items."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/definition-html-native/utterances.json b/fixtures/definition-html-native/utterances.json
index 269bed0..883e23e 100644
--- a/fixtures/definition-html-native/utterances.json
+++ b/fixtures/definition-html-native/utterances.json
@@ -1,5 +1,16 @@
-[
-  {
-    "plain": "A structure that contains an enumeration of related content items."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "A structure that contains an enumeration of related content items."
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "A structure that contains an enumeration of related content items."
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/definition-role-aria/utterances.json b/fixtures/definition-role-aria/utterances.json
index 269bed0..883e23e 100644
--- a/fixtures/definition-role-aria/utterances.json
+++ b/fixtures/definition-role-aria/utterances.json
@@ -1,5 +1,16 @@
-[
-  {
-    "plain": "A structure that contains an enumeration of related content items."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "A structure that contains an enumeration of related content items."
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "A structure that contains an enumeration of related content items."
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/details-html-native/utterances.json b/fixtures/details-html-native/utterances.json
index f02d095..2d09427 100644
--- a/fixtures/details-html-native/utterances.json
+++ b/fixtures/details-html-native/utterances.json
@@ -1,5 +1,68 @@
-[
-  {
-    "plain": "Additional details the reader can expand."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the details."
+      },
+      {
+        "plain": "Additional details the reader can expand."
+      },
+      {
+        "plain": "End of the details."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "skip": [
+            "details"
+          ]
+        },
+        "utterances": []
+      },
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "Additional details the reader can expand."
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the details."
+      },
+      {
+        "ssml": "Additional details the reader can expand."
+      },
+      {
+        "ssml": "End of the details."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "skip": [
+            "details"
+          ]
+        },
+        "utterances": []
+      },
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "Additional details the reader can expand."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/endnotes-epub-type/gnd.json b/fixtures/endnotes-epub-type/gnd.json
index e4d319d..d775136 100644
--- a/fixtures/endnotes-epub-type/gnd.json
+++ b/fixtures/endnotes-epub-type/gnd.json
@@ -1,41 +1,48 @@
 {
   "role": [
-    "section",
-    "endnotes"
+    "body"
   ],
   "children": [
     {
       "role": [
-        "list"
+        "section",
+        "endnotes"
       ],
       "children": [
         {
           "role": [
-            "listItem"
+            "list"
           ],
           "children": [
             {
               "role": [
-                "aside",
-                "footnote"
+                "listItem"
               ],
-              "id": "note1",
-              "text": "See introduction for background."
-            }
-          ]
-        },
-        {
-          "role": [
-            "listItem"
-          ],
-          "children": [
+              "children": [
+                {
+                  "id": "note1",
+                  "text": "See introduction for background.",
+                  "role": [
+                    "aside",
+                    "footnote"
+                  ]
+                }
+              ]
+            },
             {
               "role": [
-                "aside",
-                "footnote"
+                "listItem"
               ],
-              "id": "note2",
-              "text": "See chapter three for details."
+              "children": [
+                {
+                  "id": "note2",
+                  "text": "See chapter three for details.",
+                  "role": [
+                    "aside",
+                    "footnote"
+                  ]
+                }
+              ]
             }
           ]
         }
diff --git a/fixtures/endnotes-epub-type/input.html b/fixtures/endnotes-epub-type/input.xhtml
similarity index 100%
rename from fixtures/endnotes-epub-type/input.html
rename to fixtures/endnotes-epub-type/input.xhtml
diff --git a/fixtures/endnotes-epub-type/utterances.json b/fixtures/endnotes-epub-type/utterances.json
index 24e0548..82804fa 100644
--- a/fixtures/endnotes-epub-type/utterances.json
+++ b/fixtures/endnotes-epub-type/utterances.json
@@ -1,8 +1,140 @@
-[
-  {
-    "plain": "See introduction for background."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the endnotes."
+      },
+      {
+        "plain": "See introduction for background."
+      },
+      {
+        "plain": "See chapter three for details."
+      },
+      {
+        "plain": "End of the endnotes."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "skip": [
+            "aside"
+          ]
+        },
+        "utterances": [
+          {
+            "plain": "Start of the endnotes."
+          },
+          {
+            "plain": "End of the endnotes."
+          }
+        ]
+      },
+      {
+        "options": {
+          "skip": [
+            "endnotes"
+          ]
+        },
+        "utterances": []
+      },
+      {
+        "options": {
+          "skip": [
+            "footnote"
+          ]
+        },
+        "utterances": [
+          {
+            "plain": "Start of the endnotes."
+          },
+          {
+            "plain": "End of the endnotes."
+          }
+        ]
+      },
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "See introduction for background."
+          },
+          {
+            "plain": "See chapter three for details."
+          }
+        ]
+      }
+    ]
   },
-  {
-    "plain": "See chapter three for details."
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the endnotes."
+      },
+      {
+        "ssml": "See introduction for background."
+      },
+      {
+        "ssml": "See chapter three for details."
+      },
+      {
+        "ssml": "End of the endnotes."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "skip": [
+            "aside"
+          ]
+        },
+        "utterances": [
+          {
+            "ssml": "Start of the endnotes."
+          },
+          {
+            "ssml": "End of the endnotes."
+          }
+        ]
+      },
+      {
+        "options": {
+          "skip": [
+            "endnotes"
+          ]
+        },
+        "utterances": []
+      },
+      {
+        "options": {
+          "skip": [
+            "footnote"
+          ]
+        },
+        "utterances": [
+          {
+            "ssml": "Start of the endnotes."
+          },
+          {
+            "ssml": "End of the endnotes."
+          }
+        ]
+      },
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "See introduction for background."
+          },
+          {
+            "ssml": "See chapter three for details."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/endnotes-role-aria/utterances.json b/fixtures/endnotes-role-aria/utterances.json
index 24e0548..99379f8 100644
--- a/fixtures/endnotes-role-aria/utterances.json
+++ b/fixtures/endnotes-role-aria/utterances.json
@@ -1,8 +1,110 @@
-[
-  {
-    "plain": "See introduction for background."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the endnotes."
+      },
+      {
+        "plain": "See introduction for background."
+      },
+      {
+        "plain": "See chapter three for details."
+      },
+      {
+        "plain": "End of the endnotes."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "skip": [
+            "endnotes"
+          ]
+        },
+        "utterances": []
+      },
+      {
+        "options": {
+          "skip": [
+            "footnote"
+          ]
+        },
+        "utterances": [
+          {
+            "plain": "Start of the endnotes."
+          },
+          {
+            "plain": "End of the endnotes."
+          }
+        ]
+      },
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "See introduction for background."
+          },
+          {
+            "plain": "See chapter three for details."
+          }
+        ]
+      }
+    ]
   },
-  {
-    "plain": "See chapter three for details."
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the endnotes."
+      },
+      {
+        "ssml": "See introduction for background."
+      },
+      {
+        "ssml": "See chapter three for details."
+      },
+      {
+        "ssml": "End of the endnotes."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "skip": [
+            "endnotes"
+          ]
+        },
+        "utterances": []
+      },
+      {
+        "options": {
+          "skip": [
+            "footnote"
+          ]
+        },
+        "utterances": [
+          {
+            "ssml": "Start of the endnotes."
+          },
+          {
+            "ssml": "End of the endnotes."
+          }
+        ]
+      },
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "See introduction for background."
+          },
+          {
+            "ssml": "See chapter three for details."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/epigraph-epub-type/gnd.json b/fixtures/epigraph-epub-type/gnd.json
index cc39a06..3876a7d 100644
--- a/fixtures/epigraph-epub-type/gnd.json
+++ b/fixtures/epigraph-epub-type/gnd.json
@@ -1,6 +1,13 @@
 {
   "role": [
-    "epigraph"
+    "body"
   ],
-  "text": "A lighthouse is a compromise with the sea. — Anonymous"
+  "children": [
+    {
+      "text": "A lighthouse is a compromise with the sea. — Anonymous",
+      "role": [
+        "epigraph"
+      ]
+    }
+  ]
 }
diff --git a/fixtures/epigraph-epub-type/input.html b/fixtures/epigraph-epub-type/input.xhtml
similarity index 100%
rename from fixtures/epigraph-epub-type/input.html
rename to fixtures/epigraph-epub-type/input.xhtml
diff --git a/fixtures/epigraph-epub-type/utterances.json b/fixtures/epigraph-epub-type/utterances.json
index e5c70d9..ed0b572 100644
--- a/fixtures/epigraph-epub-type/utterances.json
+++ b/fixtures/epigraph-epub-type/utterances.json
@@ -1,5 +1,46 @@
-[
-  {
-    "plain": "A lighthouse is a compromise with the sea. — Anonymous"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Epigraph."
+      },
+      {
+        "plain": "A lighthouse is a compromise with the sea. — Anonymous"
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "A lighthouse is a compromise with the sea. — Anonymous"
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Epigraph."
+      },
+      {
+        "ssml": "A lighthouse is a compromise with the sea. — Anonymous"
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "A lighthouse is a compromise with the sea. — Anonymous"
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/epigraph-role-aria/utterances.json b/fixtures/epigraph-role-aria/utterances.json
index e5c70d9..ed0b572 100644
--- a/fixtures/epigraph-role-aria/utterances.json
+++ b/fixtures/epigraph-role-aria/utterances.json
@@ -1,5 +1,46 @@
-[
-  {
-    "plain": "A lighthouse is a compromise with the sea. — Anonymous"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Epigraph."
+      },
+      {
+        "plain": "A lighthouse is a compromise with the sea. — Anonymous"
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "A lighthouse is a compromise with the sea. — Anonymous"
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Epigraph."
+      },
+      {
+        "ssml": "A lighthouse is a compromise with the sea. — Anonymous"
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "A lighthouse is a compromise with the sea. — Anonymous"
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/epilogue-epub-type/gnd.json b/fixtures/epilogue-epub-type/gnd.json
index d6246aa..6e4b7ce 100644
--- a/fixtures/epilogue-epub-type/gnd.json
+++ b/fixtures/epilogue-epub-type/gnd.json
@@ -1,6 +1,13 @@
 {
   "role": [
-    "epilogue"
+    "body"
   ],
-  "text": "The lamp still turns, though no one climbs the stairs anymore."
+  "children": [
+    {
+      "text": "The lamp still turns, though no one climbs the stairs anymore.",
+      "role": [
+        "epilogue"
+      ]
+    }
+  ]
 }
diff --git a/fixtures/epilogue-epub-type/input.html b/fixtures/epilogue-epub-type/input.xhtml
similarity index 100%
rename from fixtures/epilogue-epub-type/input.html
rename to fixtures/epilogue-epub-type/input.xhtml
diff --git a/fixtures/epilogue-epub-type/utterances.json b/fixtures/epilogue-epub-type/utterances.json
index d2d00eb..bd37864 100644
--- a/fixtures/epilogue-epub-type/utterances.json
+++ b/fixtures/epilogue-epub-type/utterances.json
@@ -1,5 +1,52 @@
-[
-  {
-    "plain": "The lamp still turns, though no one climbs the stairs anymore."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the epilogue."
+      },
+      {
+        "plain": "The lamp still turns, though no one climbs the stairs anymore."
+      },
+      {
+        "plain": "End of the epilogue."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "The lamp still turns, though no one climbs the stairs anymore."
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the epilogue."
+      },
+      {
+        "ssml": "The lamp still turns, though no one climbs the stairs anymore."
+      },
+      {
+        "ssml": "End of the epilogue."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "The lamp still turns, though no one climbs the stairs anymore."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/epilogue-role-aria/utterances.json b/fixtures/epilogue-role-aria/utterances.json
index d2d00eb..bd37864 100644
--- a/fixtures/epilogue-role-aria/utterances.json
+++ b/fixtures/epilogue-role-aria/utterances.json
@@ -1,5 +1,52 @@
-[
-  {
-    "plain": "The lamp still turns, though no one climbs the stairs anymore."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the epilogue."
+      },
+      {
+        "plain": "The lamp still turns, though no one climbs the stairs anymore."
+      },
+      {
+        "plain": "End of the epilogue."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "The lamp still turns, though no one climbs the stairs anymore."
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the epilogue."
+      },
+      {
+        "ssml": "The lamp still turns, though no one climbs the stairs anymore."
+      },
+      {
+        "ssml": "End of the epilogue."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "The lamp still turns, though no one climbs the stairs anymore."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/errata-epub-type/gnd.json b/fixtures/errata-epub-type/gnd.json
index 59ecbbb..ea2c376 100644
--- a/fixtures/errata-epub-type/gnd.json
+++ b/fixtures/errata-epub-type/gnd.json
@@ -1,6 +1,13 @@
 {
   "role": [
-    "errata"
+    "body"
   ],
-  "text": "Page 42: 'lightouse' should read 'lighthouse'."
+  "children": [
+    {
+      "text": "Page 42: 'lightouse' should read 'lighthouse'.",
+      "role": [
+        "errata"
+      ]
+    }
+  ]
 }
diff --git a/fixtures/errata-epub-type/input.html b/fixtures/errata-epub-type/input.xhtml
similarity index 100%
rename from fixtures/errata-epub-type/input.html
rename to fixtures/errata-epub-type/input.xhtml
diff --git a/fixtures/errata-epub-type/utterances.json b/fixtures/errata-epub-type/utterances.json
index aa063c3..ee30ff4 100644
--- a/fixtures/errata-epub-type/utterances.json
+++ b/fixtures/errata-epub-type/utterances.json
@@ -1,5 +1,46 @@
-[
-  {
-    "plain": "Page 42: 'lightouse' should read 'lighthouse'."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Errata."
+      },
+      {
+        "plain": "Page 42: 'lightouse' should read 'lighthouse'."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "Page 42: 'lightouse' should read 'lighthouse'."
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Errata."
+      },
+      {
+        "ssml": "Page 42: 'lightouse' should read 'lighthouse'."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "Page 42: 'lightouse' should read 'lighthouse'."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/errata-role-aria/utterances.json b/fixtures/errata-role-aria/utterances.json
index aa063c3..ee30ff4 100644
--- a/fixtures/errata-role-aria/utterances.json
+++ b/fixtures/errata-role-aria/utterances.json
@@ -1,5 +1,46 @@
-[
-  {
-    "plain": "Page 42: 'lightouse' should read 'lighthouse'."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Errata."
+      },
+      {
+        "plain": "Page 42: 'lightouse' should read 'lighthouse'."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "Page 42: 'lightouse' should read 'lighthouse'."
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Errata."
+      },
+      {
+        "ssml": "Page 42: 'lightouse' should read 'lighthouse'."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "Page 42: 'lightouse' should read 'lighthouse'."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/example-epub-type/gnd.json b/fixtures/example-epub-type/gnd.json
index 139a973..d352f1f 100644
--- a/fixtures/example-epub-type/gnd.json
+++ b/fixtures/example-epub-type/gnd.json
@@ -1,6 +1,13 @@
 {
   "role": [
-    "example"
+    "body"
   ],
-  "text": "For instance, a Fresnel lens focuses light into a narrow beam."
+  "children": [
+    {
+      "text": "For instance, a Fresnel lens focuses light into a narrow beam.",
+      "role": [
+        "example"
+      ]
+    }
+  ]
 }
diff --git a/fixtures/example-epub-type/input.html b/fixtures/example-epub-type/input.xhtml
similarity index 100%
rename from fixtures/example-epub-type/input.html
rename to fixtures/example-epub-type/input.xhtml
diff --git a/fixtures/example-epub-type/utterances.json b/fixtures/example-epub-type/utterances.json
index d4f1fa6..e6891a2 100644
--- a/fixtures/example-epub-type/utterances.json
+++ b/fixtures/example-epub-type/utterances.json
@@ -1,5 +1,46 @@
-[
-  {
-    "plain": "For instance, a Fresnel lens focuses light into a narrow beam."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Example."
+      },
+      {
+        "plain": "For instance, a Fresnel lens focuses light into a narrow beam."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "For instance, a Fresnel lens focuses light into a narrow beam."
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Example."
+      },
+      {
+        "ssml": "For instance, a Fresnel lens focuses light into a narrow beam."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "For instance, a Fresnel lens focuses light into a narrow beam."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/example-role-aria/utterances.json b/fixtures/example-role-aria/utterances.json
index d4f1fa6..e6891a2 100644
--- a/fixtures/example-role-aria/utterances.json
+++ b/fixtures/example-role-aria/utterances.json
@@ -1,5 +1,46 @@
-[
-  {
-    "plain": "For instance, a Fresnel lens focuses light into a narrow beam."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Example."
+      },
+      {
+        "plain": "For instance, a Fresnel lens focuses light into a narrow beam."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "For instance, a Fresnel lens focuses light into a narrow beam."
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Example."
+      },
+      {
+        "ssml": "For instance, a Fresnel lens focuses light into a narrow beam."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "For instance, a Fresnel lens focuses light into a narrow beam."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/figure-basic-epub-type/gnd.json b/fixtures/figure-basic-epub-type/gnd.json
index 54d3788..8577c38 100644
--- a/fixtures/figure-basic-epub-type/gnd.json
+++ b/fixtures/figure-basic-epub-type/gnd.json
@@ -1,14 +1,21 @@
 {
   "role": [
-    "figure"
+    "body"
   ],
   "children": [
     {
       "role": [
-        "image"
+        "figure"
       ],
-      "imgref": "chart.png",
-      "description": "A bar chart showing sales growth"
+      "children": [
+        {
+          "imgref": "chart.png",
+          "role": [
+            "image"
+          ],
+          "description": "A bar chart showing sales growth"
+        }
+      ]
     }
   ]
 }
diff --git a/fixtures/figure-basic-epub-type/input.html b/fixtures/figure-basic-epub-type/input.xhtml
similarity index 100%
rename from fixtures/figure-basic-epub-type/input.html
rename to fixtures/figure-basic-epub-type/input.xhtml
diff --git a/fixtures/figure-basic-epub-type/utterances.json b/fixtures/figure-basic-epub-type/utterances.json
index 4265c35..2f6bdd5 100644
--- a/fixtures/figure-basic-epub-type/utterances.json
+++ b/fixtures/figure-basic-epub-type/utterances.json
@@ -1,5 +1,52 @@
-[
-  {
-    "plain": "A bar chart showing sales growth"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the figure."
+      },
+      {
+        "plain": "A bar chart showing sales growth"
+      },
+      {
+        "plain": "End of the figure."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "A bar chart showing sales growth"
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the figure."
+      },
+      {
+        "ssml": "A bar chart showing sales growth"
+      },
+      {
+        "ssml": "End of the figure."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "A bar chart showing sales growth"
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/figure-basic-html-native/utterances.json b/fixtures/figure-basic-html-native/utterances.json
index 4265c35..2f6bdd5 100644
--- a/fixtures/figure-basic-html-native/utterances.json
+++ b/fixtures/figure-basic-html-native/utterances.json
@@ -1,5 +1,52 @@
-[
-  {
-    "plain": "A bar chart showing sales growth"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the figure."
+      },
+      {
+        "plain": "A bar chart showing sales growth"
+      },
+      {
+        "plain": "End of the figure."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "A bar chart showing sales growth"
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the figure."
+      },
+      {
+        "ssml": "A bar chart showing sales growth"
+      },
+      {
+        "ssml": "End of the figure."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "A bar chart showing sales growth"
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/figure-basic-role-aria/utterances.json b/fixtures/figure-basic-role-aria/utterances.json
index 4265c35..2f6bdd5 100644
--- a/fixtures/figure-basic-role-aria/utterances.json
+++ b/fixtures/figure-basic-role-aria/utterances.json
@@ -1,5 +1,52 @@
-[
-  {
-    "plain": "A bar chart showing sales growth"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the figure."
+      },
+      {
+        "plain": "A bar chart showing sales growth"
+      },
+      {
+        "plain": "End of the figure."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "A bar chart showing sales growth"
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the figure."
+      },
+      {
+        "ssml": "A bar chart showing sales growth"
+      },
+      {
+        "ssml": "End of the figure."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "A bar chart showing sales growth"
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/figure-caption-html-native/utterances.json b/fixtures/figure-caption-html-native/utterances.json
index ce3a3d2..0ffaafc 100644
--- a/fixtures/figure-caption-html-native/utterances.json
+++ b/fixtures/figure-caption-html-native/utterances.json
@@ -1,5 +1,52 @@
-[
-  {
-    "plain": "ASCII Art of a cat face"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the figure."
+      },
+      {
+        "plain": "End of the figure."
+      },
+      {
+        "plain": "ASCII Art of a cat face"
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "ASCII Art of a cat face"
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the figure."
+      },
+      {
+        "ssml": "End of the figure."
+      },
+      {
+        "ssml": "ASCII Art of a cat face"
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "ASCII Art of a cat face"
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/figure-caption-role-aria/utterances.json b/fixtures/figure-caption-role-aria/utterances.json
index ce3a3d2..0ffaafc 100644
--- a/fixtures/figure-caption-role-aria/utterances.json
+++ b/fixtures/figure-caption-role-aria/utterances.json
@@ -1,5 +1,52 @@
-[
-  {
-    "plain": "ASCII Art of a cat face"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the figure."
+      },
+      {
+        "plain": "End of the figure."
+      },
+      {
+        "plain": "ASCII Art of a cat face"
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "ASCII Art of a cat face"
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the figure."
+      },
+      {
+        "ssml": "End of the figure."
+      },
+      {
+        "ssml": "ASCII Art of a cat face"
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "ASCII Art of a cat face"
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/figure-describedby/utterances.json b/fixtures/figure-describedby/utterances.json
index 8336cd9..6d6c79f 100644
--- a/fixtures/figure-describedby/utterances.json
+++ b/fixtures/figure-describedby/utterances.json
@@ -1,8 +1,64 @@
-[
-  {
-    "plain": "Sales chart"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the figure."
+      },
+      {
+        "plain": "Sales chart"
+      },
+      {
+        "plain": "End of the figure."
+      },
+      {
+        "plain": "Full audio description: sales grew 12% year over year, driven primarily by the Q4 holiday season."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "Sales chart"
+          },
+          {
+            "plain": "Full audio description: sales grew 12% year over year, driven primarily by the Q4 holiday season."
+          }
+        ]
+      }
+    ]
   },
-  {
-    "plain": "Full audio description: sales grew 12% year over year, driven primarily by the Q4 holiday season."
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the figure."
+      },
+      {
+        "ssml": "Sales chart"
+      },
+      {
+        "ssml": "End of the figure."
+      },
+      {
+        "ssml": "Full audio description: sales grew 12% year over year, driven primarily by the Q4 holiday season."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "Sales chart"
+          },
+          {
+            "ssml": "Full audio description: sales grew 12% year over year, driven primarily by the Q4 holiday season."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/footnote-epub-type/gnd.json b/fixtures/footnote-epub-type/gnd.json
index 6c026f2..b0c4f22 100644
--- a/fixtures/footnote-epub-type/gnd.json
+++ b/fixtures/footnote-epub-type/gnd.json
@@ -1,28 +1,31 @@
 {
+  "role": [
+    "body"
+  ],
   "children": [
     {
-      "role": [
-        "paragraph"
-      ],
       "text": {
+        "language": "en",
         "plain": "This text has a footnote.",
-        "ssml": "This text has a footnote <readium:noteref id=\"note1\" />.",
-        "language": "en"
+        "ssml": "This text has a footnote <readium:noteref id=\"note1\" />."
       },
+      "role": [
+        "paragraph"
+      ],
       "children": [
         {
+          "id": "note1",
+          "text": "[1]",
           "role": [
             "noteref"
           ],
-          "id": "note1",
-          "text": "[1]",
           "children": [
             {
+              "text": "Text of the footnote.",
               "role": [
                 "aside",
                 "footnote"
-              ],
-              "text": "Text of the footnote."
+              ]
             }
           ]
         }
diff --git a/fixtures/footnote-epub-type/input.html b/fixtures/footnote-epub-type/input.xhtml
similarity index 100%
rename from fixtures/footnote-epub-type/input.html
rename to fixtures/footnote-epub-type/input.xhtml
diff --git a/fixtures/footnote-epub-type/meta.json b/fixtures/footnote-epub-type/meta.json
index 1748196..3731633 100644
--- a/fixtures/footnote-epub-type/meta.json
+++ b/fixtures/footnote-epub-type/meta.json
@@ -7,6 +7,5 @@
     "noteref"
   ],
   "sourceRef": "https://github.com/readium/guided-navigation/tree/main/examples/read-aloud",
-  "inputKind": "document",
-  "skip": ["footnote"]
+  "inputKind": "document"
 }
diff --git a/fixtures/footnote-epub-type/utterances-skipped.json b/fixtures/footnote-epub-type/utterances-skipped.json
deleted file mode 100644
index 70c490e..0000000
--- a/fixtures/footnote-epub-type/utterances-skipped.json
+++ /dev/null
@@ -1,6 +0,0 @@
-[
-  {
-    "plain": "This text has a footnote.",
-    "language": "en"
-  }
-]
diff --git a/fixtures/footnote-epub-type/utterances.json b/fixtures/footnote-epub-type/utterances.json
index b9d07c3..5822880 100644
--- a/fixtures/footnote-epub-type/utterances.json
+++ b/fixtures/footnote-epub-type/utterances.json
@@ -1,15 +1,194 @@
-[
-  {
-    "plain": "This text has a footnote.",
-    "language": "en"
+{
+  "plain": {
+    "base": [
+      {
+        "language": "en",
+        "plain": "This text has a footnote."
+      },
+      {
+        "plain": "Start of the footnote."
+      },
+      {
+        "plain": "Text of the footnote."
+      },
+      {
+        "plain": "End of the footnote."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "skip": [
+            "aside"
+          ]
+        },
+        "utterances": [
+          {
+            "language": "en",
+            "plain": "This text has a footnote."
+          }
+        ]
+      },
+      {
+        "options": {
+          "skip": [
+            "footnote"
+          ]
+        },
+        "utterances": [
+          {
+            "language": "en",
+            "plain": "This text has a footnote."
+          }
+        ]
+      },
+      {
+        "options": {
+          "skip": [
+            "noteref"
+          ]
+        },
+        "utterances": [
+          {
+            "language": "en",
+            "plain": "This text has a footnote."
+          }
+        ]
+      },
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "language": "en",
+            "plain": "This text has a footnote."
+          },
+          {
+            "plain": "Text of the footnote."
+          }
+        ]
+      },
+      {
+        "options": {
+          "interruptSentence": true
+        },
+        "utterances": [
+          {
+            "language": "en",
+            "plain": "This text has a footnote"
+          },
+          {
+            "plain": "Start of the footnote."
+          },
+          {
+            "plain": "Text of the footnote."
+          },
+          {
+            "plain": "End of the footnote."
+          },
+          {
+            "language": "en",
+            "plain": "."
+          }
+        ]
+      }
+    ]
   },
-  {
-    "plain": "Start of the footnote."
-  },
-  {
-    "plain": "Text of the footnote."
-  },
-  {
-    "plain": "End of the footnote."
+  "ssml": {
+    "base": [
+      {
+        "language": "en",
+        "ssml": "This text has a footnote."
+      },
+      {
+        "ssml": "Start of the footnote."
+      },
+      {
+        "ssml": "Text of the footnote."
+      },
+      {
+        "ssml": "End of the footnote."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "skip": [
+            "aside"
+          ]
+        },
+        "utterances": [
+          {
+            "language": "en",
+            "ssml": "This text has a footnote."
+          }
+        ]
+      },
+      {
+        "options": {
+          "skip": [
+            "footnote"
+          ]
+        },
+        "utterances": [
+          {
+            "language": "en",
+            "ssml": "This text has a footnote."
+          }
+        ]
+      },
+      {
+        "options": {
+          "skip": [
+            "noteref"
+          ]
+        },
+        "utterances": [
+          {
+            "language": "en",
+            "ssml": "This text has a footnote."
+          }
+        ]
+      },
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "language": "en",
+            "ssml": "This text has a footnote."
+          },
+          {
+            "ssml": "Text of the footnote."
+          }
+        ]
+      },
+      {
+        "options": {
+          "interruptSentence": true
+        },
+        "utterances": [
+          {
+            "language": "en",
+            "ssml": "This text has a footnote"
+          },
+          {
+            "ssml": "Start of the footnote."
+          },
+          {
+            "ssml": "Text of the footnote."
+          },
+          {
+            "ssml": "End of the footnote."
+          },
+          {
+            "language": "en",
+            "ssml": "."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/footnote-role-aria/meta.json b/fixtures/footnote-role-aria/meta.json
index 3fa217c..8175572 100644
--- a/fixtures/footnote-role-aria/meta.json
+++ b/fixtures/footnote-role-aria/meta.json
@@ -7,6 +7,5 @@
     "noteref"
   ],
   "sourceRef": "https://github.com/readium/guided-navigation/tree/main/examples/read-aloud",
-  "inputKind": "fragment",
-  "skip": ["footnote"]
+  "inputKind": "fragment"
 }
diff --git a/fixtures/footnote-role-aria/utterances-skipped.json b/fixtures/footnote-role-aria/utterances-skipped.json
deleted file mode 100644
index 70c490e..0000000
--- a/fixtures/footnote-role-aria/utterances-skipped.json
+++ /dev/null
@@ -1,6 +0,0 @@
-[
-  {
-    "plain": "This text has a footnote.",
-    "language": "en"
-  }
-]
diff --git a/fixtures/footnote-role-aria/utterances.json b/fixtures/footnote-role-aria/utterances.json
index b9d07c3..5822880 100644
--- a/fixtures/footnote-role-aria/utterances.json
+++ b/fixtures/footnote-role-aria/utterances.json
@@ -1,15 +1,194 @@
-[
-  {
-    "plain": "This text has a footnote.",
-    "language": "en"
+{
+  "plain": {
+    "base": [
+      {
+        "language": "en",
+        "plain": "This text has a footnote."
+      },
+      {
+        "plain": "Start of the footnote."
+      },
+      {
+        "plain": "Text of the footnote."
+      },
+      {
+        "plain": "End of the footnote."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "skip": [
+            "aside"
+          ]
+        },
+        "utterances": [
+          {
+            "language": "en",
+            "plain": "This text has a footnote."
+          }
+        ]
+      },
+      {
+        "options": {
+          "skip": [
+            "footnote"
+          ]
+        },
+        "utterances": [
+          {
+            "language": "en",
+            "plain": "This text has a footnote."
+          }
+        ]
+      },
+      {
+        "options": {
+          "skip": [
+            "noteref"
+          ]
+        },
+        "utterances": [
+          {
+            "language": "en",
+            "plain": "This text has a footnote."
+          }
+        ]
+      },
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "language": "en",
+            "plain": "This text has a footnote."
+          },
+          {
+            "plain": "Text of the footnote."
+          }
+        ]
+      },
+      {
+        "options": {
+          "interruptSentence": true
+        },
+        "utterances": [
+          {
+            "language": "en",
+            "plain": "This text has a footnote"
+          },
+          {
+            "plain": "Start of the footnote."
+          },
+          {
+            "plain": "Text of the footnote."
+          },
+          {
+            "plain": "End of the footnote."
+          },
+          {
+            "language": "en",
+            "plain": "."
+          }
+        ]
+      }
+    ]
   },
-  {
-    "plain": "Start of the footnote."
-  },
-  {
-    "plain": "Text of the footnote."
-  },
-  {
-    "plain": "End of the footnote."
+  "ssml": {
+    "base": [
+      {
+        "language": "en",
+        "ssml": "This text has a footnote."
+      },
+      {
+        "ssml": "Start of the footnote."
+      },
+      {
+        "ssml": "Text of the footnote."
+      },
+      {
+        "ssml": "End of the footnote."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "skip": [
+            "aside"
+          ]
+        },
+        "utterances": [
+          {
+            "language": "en",
+            "ssml": "This text has a footnote."
+          }
+        ]
+      },
+      {
+        "options": {
+          "skip": [
+            "footnote"
+          ]
+        },
+        "utterances": [
+          {
+            "language": "en",
+            "ssml": "This text has a footnote."
+          }
+        ]
+      },
+      {
+        "options": {
+          "skip": [
+            "noteref"
+          ]
+        },
+        "utterances": [
+          {
+            "language": "en",
+            "ssml": "This text has a footnote."
+          }
+        ]
+      },
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "language": "en",
+            "ssml": "This text has a footnote."
+          },
+          {
+            "ssml": "Text of the footnote."
+          }
+        ]
+      },
+      {
+        "options": {
+          "interruptSentence": true
+        },
+        "utterances": [
+          {
+            "language": "en",
+            "ssml": "This text has a footnote"
+          },
+          {
+            "ssml": "Start of the footnote."
+          },
+          {
+            "ssml": "Text of the footnote."
+          },
+          {
+            "ssml": "End of the footnote."
+          },
+          {
+            "language": "en",
+            "ssml": "."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/foreword-epub-type/gnd.json b/fixtures/foreword-epub-type/gnd.json
index 1bee105..9a74352 100644
--- a/fixtures/foreword-epub-type/gnd.json
+++ b/fixtures/foreword-epub-type/gnd.json
@@ -1,6 +1,13 @@
 {
   "role": [
-    "foreword"
+    "body"
   ],
-  "text": "A respected maritime historian introduces this account of the coastline's lighthouses."
+  "children": [
+    {
+      "text": "A respected maritime historian introduces this account of the coastline's lighthouses.",
+      "role": [
+        "foreword"
+      ]
+    }
+  ]
 }
diff --git a/fixtures/foreword-epub-type/input.html b/fixtures/foreword-epub-type/input.xhtml
similarity index 100%
rename from fixtures/foreword-epub-type/input.html
rename to fixtures/foreword-epub-type/input.xhtml
diff --git a/fixtures/foreword-epub-type/utterances.json b/fixtures/foreword-epub-type/utterances.json
index 9dd5982..e38e3d5 100644
--- a/fixtures/foreword-epub-type/utterances.json
+++ b/fixtures/foreword-epub-type/utterances.json
@@ -1,5 +1,16 @@
-[
-  {
-    "plain": "A respected maritime historian introduces this account of the coastline's lighthouses."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "A respected maritime historian introduces this account of the coastline's lighthouses."
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "A respected maritime historian introduces this account of the coastline's lighthouses."
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/foreword-role-aria/utterances.json b/fixtures/foreword-role-aria/utterances.json
index 9dd5982..e38e3d5 100644
--- a/fixtures/foreword-role-aria/utterances.json
+++ b/fixtures/foreword-role-aria/utterances.json
@@ -1,5 +1,16 @@
-[
-  {
-    "plain": "A respected maritime historian introduces this account of the coastline's lighthouses."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "A respected maritime historian introduces this account of the coastline's lighthouses."
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "A respected maritime historian introduces this account of the coastline's lighthouses."
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/glossary-epub-type/gnd.json b/fixtures/glossary-epub-type/gnd.json
index e1b8e44..3a1ab77 100644
--- a/fixtures/glossary-epub-type/gnd.json
+++ b/fixtures/glossary-epub-type/gnd.json
@@ -1,31 +1,38 @@
 {
   "role": [
-    "glossary"
+    "body"
   ],
   "children": [
     {
       "role": [
-        "term"
+        "glossary"
       ],
-      "text": "Fresnel lens"
-    },
-    {
-      "role": [
-        "definition"
-      ],
-      "text": "A compact lens for focusing light."
-    },
-    {
-      "role": [
-        "term"
-      ],
-      "text": "Keeper"
-    },
-    {
-      "role": [
-        "definition"
-      ],
-      "text": "A person responsible for maintaining a lighthouse."
+      "children": [
+        {
+          "text": "Fresnel lens",
+          "role": [
+            "term"
+          ]
+        },
+        {
+          "text": "A compact lens for focusing light.",
+          "role": [
+            "definition"
+          ]
+        },
+        {
+          "text": "Keeper",
+          "role": [
+            "term"
+          ]
+        },
+        {
+          "text": "A person responsible for maintaining a lighthouse.",
+          "role": [
+            "definition"
+          ]
+        }
+      ]
     }
   ]
 }
diff --git a/fixtures/glossary-epub-type/input.html b/fixtures/glossary-epub-type/input.xhtml
similarity index 100%
rename from fixtures/glossary-epub-type/input.html
rename to fixtures/glossary-epub-type/input.xhtml
diff --git a/fixtures/glossary-epub-type/utterances.json b/fixtures/glossary-epub-type/utterances.json
index cdc7709..250cbe5 100644
--- a/fixtures/glossary-epub-type/utterances.json
+++ b/fixtures/glossary-epub-type/utterances.json
@@ -1,14 +1,88 @@
-[
-  {
-    "plain": "Fresnel lens"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the glossary."
+      },
+      {
+        "plain": "Fresnel lens"
+      },
+      {
+        "plain": "A compact lens for focusing light."
+      },
+      {
+        "plain": "Keeper"
+      },
+      {
+        "plain": "A person responsible for maintaining a lighthouse."
+      },
+      {
+        "plain": "End of the glossary."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "Fresnel lens"
+          },
+          {
+            "plain": "A compact lens for focusing light."
+          },
+          {
+            "plain": "Keeper"
+          },
+          {
+            "plain": "A person responsible for maintaining a lighthouse."
+          }
+        ]
+      }
+    ]
   },
-  {
-    "plain": "A compact lens for focusing light."
-  },
-  {
-    "plain": "Keeper"
-  },
-  {
-    "plain": "A person responsible for maintaining a lighthouse."
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the glossary."
+      },
+      {
+        "ssml": "Fresnel lens"
+      },
+      {
+        "ssml": "A compact lens for focusing light."
+      },
+      {
+        "ssml": "Keeper"
+      },
+      {
+        "ssml": "A person responsible for maintaining a lighthouse."
+      },
+      {
+        "ssml": "End of the glossary."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "Fresnel lens"
+          },
+          {
+            "ssml": "A compact lens for focusing light."
+          },
+          {
+            "ssml": "Keeper"
+          },
+          {
+            "ssml": "A person responsible for maintaining a lighthouse."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/glossary-role-aria/utterances.json b/fixtures/glossary-role-aria/utterances.json
index cdc7709..250cbe5 100644
--- a/fixtures/glossary-role-aria/utterances.json
+++ b/fixtures/glossary-role-aria/utterances.json
@@ -1,14 +1,88 @@
-[
-  {
-    "plain": "Fresnel lens"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the glossary."
+      },
+      {
+        "plain": "Fresnel lens"
+      },
+      {
+        "plain": "A compact lens for focusing light."
+      },
+      {
+        "plain": "Keeper"
+      },
+      {
+        "plain": "A person responsible for maintaining a lighthouse."
+      },
+      {
+        "plain": "End of the glossary."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "Fresnel lens"
+          },
+          {
+            "plain": "A compact lens for focusing light."
+          },
+          {
+            "plain": "Keeper"
+          },
+          {
+            "plain": "A person responsible for maintaining a lighthouse."
+          }
+        ]
+      }
+    ]
   },
-  {
-    "plain": "A compact lens for focusing light."
-  },
-  {
-    "plain": "Keeper"
-  },
-  {
-    "plain": "A person responsible for maintaining a lighthouse."
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the glossary."
+      },
+      {
+        "ssml": "Fresnel lens"
+      },
+      {
+        "ssml": "A compact lens for focusing light."
+      },
+      {
+        "ssml": "Keeper"
+      },
+      {
+        "ssml": "A person responsible for maintaining a lighthouse."
+      },
+      {
+        "ssml": "End of the glossary."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "Fresnel lens"
+          },
+          {
+            "ssml": "A compact lens for focusing light."
+          },
+          {
+            "ssml": "Keeper"
+          },
+          {
+            "ssml": "A person responsible for maintaining a lighthouse."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/glossref-epub-type/gnd.json b/fixtures/glossref-epub-type/gnd.json
index 1fc0c06..4f73e9f 100644
--- a/fixtures/glossref-epub-type/gnd.json
+++ b/fixtures/glossref-epub-type/gnd.json
@@ -1,7 +1,14 @@
 {
   "role": [
-    "glossref"
+    "body"
   ],
-  "text": "See glossary: Fresnel lens",
-  "textref": "#fresnel-lens"
+  "children": [
+    {
+      "textref": "#fresnel-lens",
+      "text": "See glossary: Fresnel lens",
+      "role": [
+        "glossref"
+      ]
+    }
+  ]
 }
diff --git a/fixtures/glossref-epub-type/input.html b/fixtures/glossref-epub-type/input.xhtml
similarity index 100%
rename from fixtures/glossref-epub-type/input.html
rename to fixtures/glossref-epub-type/input.xhtml
diff --git a/fixtures/glossref-epub-type/utterances.json b/fixtures/glossref-epub-type/utterances.json
index d210f59..7c28872 100644
--- a/fixtures/glossref-epub-type/utterances.json
+++ b/fixtures/glossref-epub-type/utterances.json
@@ -1,5 +1,16 @@
-[
-  {
-    "plain": "See glossary: Fresnel lens"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "See glossary: Fresnel lens"
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "See glossary: Fresnel lens"
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/glossref-role-aria/utterances.json b/fixtures/glossref-role-aria/utterances.json
index d210f59..7c28872 100644
--- a/fixtures/glossref-role-aria/utterances.json
+++ b/fixtures/glossref-role-aria/utterances.json
@@ -1,5 +1,16 @@
-[
-  {
-    "plain": "See glossary: Fresnel lens"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "See glossary: Fresnel lens"
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "See glossary: Fresnel lens"
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/header-html-native/utterances.json b/fixtures/header-html-native/utterances.json
index 6f02f7e..bafbf7a 100644
--- a/fixtures/header-html-native/utterances.json
+++ b/fixtures/header-html-native/utterances.json
@@ -1,5 +1,16 @@
-[
-  {
-    "plain": "Chapter One"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Chapter One"
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Chapter One"
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/heading-html-native/utterances.json b/fixtures/heading-html-native/utterances.json
index f3fede9..943593f 100644
--- a/fixtures/heading-html-native/utterances.json
+++ b/fixtures/heading-html-native/utterances.json
@@ -1,20 +1,136 @@
-[
-  {
-    "plain": "Chapter One"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Heading level 1."
+      },
+      {
+        "plain": "Chapter One"
+      },
+      {
+        "plain": "Heading level 2."
+      },
+      {
+        "plain": "Section A"
+      },
+      {
+        "plain": "Heading level 3."
+      },
+      {
+        "plain": "Subsection i"
+      },
+      {
+        "plain": "Heading level 4."
+      },
+      {
+        "plain": "Detail heading"
+      },
+      {
+        "plain": "Heading level 5."
+      },
+      {
+        "plain": "Note heading"
+      },
+      {
+        "plain": "Heading level 6."
+      },
+      {
+        "plain": "Aside heading"
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "Chapter One"
+          },
+          {
+            "plain": "Section A"
+          },
+          {
+            "plain": "Subsection i"
+          },
+          {
+            "plain": "Detail heading"
+          },
+          {
+            "plain": "Note heading"
+          },
+          {
+            "plain": "Aside heading"
+          }
+        ]
+      }
+    ]
   },
-  {
-    "plain": "Section A"
-  },
-  {
-    "plain": "Subsection i"
-  },
-  {
-    "plain": "Detail heading"
-  },
-  {
-    "plain": "Note heading"
-  },
-  {
-    "plain": "Aside heading"
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Heading level 1."
+      },
+      {
+        "ssml": "Chapter One"
+      },
+      {
+        "ssml": "Heading level 2."
+      },
+      {
+        "ssml": "Section A"
+      },
+      {
+        "ssml": "Heading level 3."
+      },
+      {
+        "ssml": "Subsection i"
+      },
+      {
+        "ssml": "Heading level 4."
+      },
+      {
+        "ssml": "Detail heading"
+      },
+      {
+        "ssml": "Heading level 5."
+      },
+      {
+        "ssml": "Note heading"
+      },
+      {
+        "ssml": "Heading level 6."
+      },
+      {
+        "ssml": "Aside heading"
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "Chapter One"
+          },
+          {
+            "ssml": "Section A"
+          },
+          {
+            "ssml": "Subsection i"
+          },
+          {
+            "ssml": "Detail heading"
+          },
+          {
+            "ssml": "Note heading"
+          },
+          {
+            "ssml": "Aside heading"
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/heading-role-aria/utterances.json b/fixtures/heading-role-aria/utterances.json
index f3fede9..943593f 100644
--- a/fixtures/heading-role-aria/utterances.json
+++ b/fixtures/heading-role-aria/utterances.json
@@ -1,20 +1,136 @@
-[
-  {
-    "plain": "Chapter One"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Heading level 1."
+      },
+      {
+        "plain": "Chapter One"
+      },
+      {
+        "plain": "Heading level 2."
+      },
+      {
+        "plain": "Section A"
+      },
+      {
+        "plain": "Heading level 3."
+      },
+      {
+        "plain": "Subsection i"
+      },
+      {
+        "plain": "Heading level 4."
+      },
+      {
+        "plain": "Detail heading"
+      },
+      {
+        "plain": "Heading level 5."
+      },
+      {
+        "plain": "Note heading"
+      },
+      {
+        "plain": "Heading level 6."
+      },
+      {
+        "plain": "Aside heading"
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "Chapter One"
+          },
+          {
+            "plain": "Section A"
+          },
+          {
+            "plain": "Subsection i"
+          },
+          {
+            "plain": "Detail heading"
+          },
+          {
+            "plain": "Note heading"
+          },
+          {
+            "plain": "Aside heading"
+          }
+        ]
+      }
+    ]
   },
-  {
-    "plain": "Section A"
-  },
-  {
-    "plain": "Subsection i"
-  },
-  {
-    "plain": "Detail heading"
-  },
-  {
-    "plain": "Note heading"
-  },
-  {
-    "plain": "Aside heading"
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Heading level 1."
+      },
+      {
+        "ssml": "Chapter One"
+      },
+      {
+        "ssml": "Heading level 2."
+      },
+      {
+        "ssml": "Section A"
+      },
+      {
+        "ssml": "Heading level 3."
+      },
+      {
+        "ssml": "Subsection i"
+      },
+      {
+        "ssml": "Heading level 4."
+      },
+      {
+        "ssml": "Detail heading"
+      },
+      {
+        "ssml": "Heading level 5."
+      },
+      {
+        "ssml": "Note heading"
+      },
+      {
+        "ssml": "Heading level 6."
+      },
+      {
+        "ssml": "Aside heading"
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "Chapter One"
+          },
+          {
+            "ssml": "Section A"
+          },
+          {
+            "ssml": "Subsection i"
+          },
+          {
+            "ssml": "Detail heading"
+          },
+          {
+            "ssml": "Note heading"
+          },
+          {
+            "ssml": "Aside heading"
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/image-alt-html-native/utterances.json b/fixtures/image-alt-html-native/utterances.json
index 735235b..08cedd3 100644
--- a/fixtures/image-alt-html-native/utterances.json
+++ b/fixtures/image-alt-html-native/utterances.json
@@ -1,5 +1,16 @@
-[
-  {
-    "plain": "Alternative text using the alt attribute"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Alternative text using the alt attribute"
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Alternative text using the alt attribute"
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/image-decorative-empty-alt/utterances.json b/fixtures/image-decorative-empty-alt/utterances.json
index e8e200a..f3663ec 100644
--- a/fixtures/image-decorative-empty-alt/utterances.json
+++ b/fixtures/image-decorative-empty-alt/utterances.json
@@ -1,8 +1,22 @@
-[
-  {
-    "plain": "Before the divider."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Before the divider."
+      },
+      {
+        "plain": "After the divider."
+      }
+    ]
   },
-  {
-    "plain": "After the divider."
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Before the divider."
+      },
+      {
+        "ssml": "After the divider."
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/image-decorative-role-presentation/utterances.json b/fixtures/image-decorative-role-presentation/utterances.json
index e8e200a..f3663ec 100644
--- a/fixtures/image-decorative-role-presentation/utterances.json
+++ b/fixtures/image-decorative-role-presentation/utterances.json
@@ -1,8 +1,22 @@
-[
-  {
-    "plain": "Before the divider."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Before the divider."
+      },
+      {
+        "plain": "After the divider."
+      }
+    ]
   },
-  {
-    "plain": "After the divider."
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Before the divider."
+      },
+      {
+        "ssml": "After the divider."
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/image-role-aria/utterances.json b/fixtures/image-role-aria/utterances.json
index 52c07ef..25ca03a 100644
--- a/fixtures/image-role-aria/utterances.json
+++ b/fixtures/image-role-aria/utterances.json
@@ -1,5 +1,16 @@
-[
-  {
-    "plain": "Rating: 4 out of 5 stars"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Rating: 4 out of 5 stars"
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Rating: 4 out of 5 stars"
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/index-epub-type/gnd.json b/fixtures/index-epub-type/gnd.json
index cadfbaa..1f1b825 100644
--- a/fixtures/index-epub-type/gnd.json
+++ b/fixtures/index-epub-type/gnd.json
@@ -1,27 +1,34 @@
 {
   "role": [
-    "navigation",
-    "index"
+    "body"
   ],
   "children": [
     {
       "role": [
-        "list"
+        "navigation",
+        "index"
       ],
       "children": [
         {
           "role": [
-            "listItem"
+            "list"
           ],
-          "text": "Fresnel lens",
-          "textref": "chapter1.xhtml#fresnel"
-        },
-        {
-          "role": [
-            "listItem"
-          ],
-          "text": "Keepers",
-          "textref": "chapter3.xhtml#keepers"
+          "children": [
+            {
+              "textref": "chapter1.xhtml#fresnel",
+              "text": "Fresnel lens",
+              "role": [
+                "listItem"
+              ]
+            },
+            {
+              "textref": "chapter3.xhtml#keepers",
+              "text": "Keepers",
+              "role": [
+                "listItem"
+              ]
+            }
+          ]
         }
       ]
     }
diff --git a/fixtures/index-epub-type/input.html b/fixtures/index-epub-type/input.xhtml
similarity index 100%
rename from fixtures/index-epub-type/input.html
rename to fixtures/index-epub-type/input.xhtml
diff --git a/fixtures/index-epub-type/utterances.json b/fixtures/index-epub-type/utterances.json
index 2c2b474..b42bac2 100644
--- a/fixtures/index-epub-type/utterances.json
+++ b/fixtures/index-epub-type/utterances.json
@@ -1,8 +1,64 @@
-[
-  {
-    "plain": "Fresnel lens"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the index."
+      },
+      {
+        "plain": "Fresnel lens"
+      },
+      {
+        "plain": "Keepers"
+      },
+      {
+        "plain": "End of the index."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "Fresnel lens"
+          },
+          {
+            "plain": "Keepers"
+          }
+        ]
+      }
+    ]
   },
-  {
-    "plain": "Keepers"
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the index."
+      },
+      {
+        "ssml": "Fresnel lens"
+      },
+      {
+        "ssml": "Keepers"
+      },
+      {
+        "ssml": "End of the index."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "Fresnel lens"
+          },
+          {
+            "ssml": "Keepers"
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/index-role-aria/utterances.json b/fixtures/index-role-aria/utterances.json
index 2c2b474..b42bac2 100644
--- a/fixtures/index-role-aria/utterances.json
+++ b/fixtures/index-role-aria/utterances.json
@@ -1,8 +1,64 @@
-[
-  {
-    "plain": "Fresnel lens"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the index."
+      },
+      {
+        "plain": "Fresnel lens"
+      },
+      {
+        "plain": "Keepers"
+      },
+      {
+        "plain": "End of the index."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "Fresnel lens"
+          },
+          {
+            "plain": "Keepers"
+          }
+        ]
+      }
+    ]
   },
-  {
-    "plain": "Keepers"
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the index."
+      },
+      {
+        "ssml": "Fresnel lens"
+      },
+      {
+        "ssml": "Keepers"
+      },
+      {
+        "ssml": "End of the index."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "Fresnel lens"
+          },
+          {
+            "ssml": "Keepers"
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/introduction-epub-type/gnd.json b/fixtures/introduction-epub-type/gnd.json
index 4eb926f..45d2f95 100644
--- a/fixtures/introduction-epub-type/gnd.json
+++ b/fixtures/introduction-epub-type/gnd.json
@@ -1,6 +1,13 @@
 {
   "role": [
-    "introduction"
+    "body"
   ],
-  "text": "This work explores the history of coastal lighthouses."
+  "children": [
+    {
+      "text": "This work explores the history of coastal lighthouses.",
+      "role": [
+        "introduction"
+      ]
+    }
+  ]
 }
diff --git a/fixtures/introduction-epub-type/input.html b/fixtures/introduction-epub-type/input.xhtml
similarity index 100%
rename from fixtures/introduction-epub-type/input.html
rename to fixtures/introduction-epub-type/input.xhtml
diff --git a/fixtures/introduction-epub-type/utterances.json b/fixtures/introduction-epub-type/utterances.json
index 9e83f9d..67ebe97 100644
--- a/fixtures/introduction-epub-type/utterances.json
+++ b/fixtures/introduction-epub-type/utterances.json
@@ -1,5 +1,52 @@
-[
-  {
-    "plain": "This work explores the history of coastal lighthouses."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the introduction."
+      },
+      {
+        "plain": "This work explores the history of coastal lighthouses."
+      },
+      {
+        "plain": "End of the introduction."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "This work explores the history of coastal lighthouses."
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the introduction."
+      },
+      {
+        "ssml": "This work explores the history of coastal lighthouses."
+      },
+      {
+        "ssml": "End of the introduction."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "This work explores the history of coastal lighthouses."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/introduction-role-aria/utterances.json b/fixtures/introduction-role-aria/utterances.json
index 9e83f9d..67ebe97 100644
--- a/fixtures/introduction-role-aria/utterances.json
+++ b/fixtures/introduction-role-aria/utterances.json
@@ -1,5 +1,52 @@
-[
-  {
-    "plain": "This work explores the history of coastal lighthouses."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the introduction."
+      },
+      {
+        "plain": "This work explores the history of coastal lighthouses."
+      },
+      {
+        "plain": "End of the introduction."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "This work explores the history of coastal lighthouses."
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the introduction."
+      },
+      {
+        "ssml": "This work explores the history of coastal lighthouses."
+      },
+      {
+        "ssml": "End of the introduction."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "This work explores the history of coastal lighthouses."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/landmarks-epub-type/gnd.json b/fixtures/landmarks-epub-type/gnd.json
index 5a70aab..0fda2c6 100644
--- a/fixtures/landmarks-epub-type/gnd.json
+++ b/fixtures/landmarks-epub-type/gnd.json
@@ -1,34 +1,41 @@
 {
   "role": [
-    "navigation",
-    "landmarks"
+    "body"
   ],
   "children": [
     {
       "role": [
-        "list"
+        "navigation",
+        "landmarks"
       ],
       "children": [
         {
           "role": [
-            "listItem"
+            "list"
           ],
-          "text": "Cover",
-          "textref": "cover.xhtml"
-        },
-        {
-          "role": [
-            "listItem"
-          ],
-          "text": "Table of Contents",
-          "textref": "toc.xhtml"
-        },
-        {
-          "role": [
-            "listItem"
-          ],
-          "text": "Start of Content",
-          "textref": "chapter1.xhtml"
+          "children": [
+            {
+              "textref": "cover.xhtml",
+              "text": "Cover",
+              "role": [
+                "listItem"
+              ]
+            },
+            {
+              "textref": "toc.xhtml",
+              "text": "Table of Contents",
+              "role": [
+                "listItem"
+              ]
+            },
+            {
+              "textref": "chapter1.xhtml",
+              "text": "Start of Content",
+              "role": [
+                "listItem"
+              ]
+            }
+          ]
         }
       ]
     }
diff --git a/fixtures/landmarks-epub-type/input.html b/fixtures/landmarks-epub-type/input.xhtml
similarity index 100%
rename from fixtures/landmarks-epub-type/input.html
rename to fixtures/landmarks-epub-type/input.xhtml
diff --git a/fixtures/landmarks-epub-type/utterances.json b/fixtures/landmarks-epub-type/utterances.json
index cf62d19..698f4d5 100644
--- a/fixtures/landmarks-epub-type/utterances.json
+++ b/fixtures/landmarks-epub-type/utterances.json
@@ -1,11 +1,92 @@
-[
-  {
-    "plain": "Cover"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the landmarks."
+      },
+      {
+        "plain": "Cover"
+      },
+      {
+        "plain": "Table of Contents"
+      },
+      {
+        "plain": "Start of Content"
+      },
+      {
+        "plain": "End of the landmarks."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "skip": [
+            "landmarks"
+          ]
+        },
+        "utterances": []
+      },
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "Cover"
+          },
+          {
+            "plain": "Table of Contents"
+          },
+          {
+            "plain": "Start of Content"
+          }
+        ]
+      }
+    ]
   },
-  {
-    "plain": "Table of Contents"
-  },
-  {
-    "plain": "Start of Content"
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the landmarks."
+      },
+      {
+        "ssml": "Cover"
+      },
+      {
+        "ssml": "Table of Contents"
+      },
+      {
+        "ssml": "Start of Content"
+      },
+      {
+        "ssml": "End of the landmarks."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "skip": [
+            "landmarks"
+          ]
+        },
+        "utterances": []
+      },
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "Cover"
+          },
+          {
+            "ssml": "Table of Contents"
+          },
+          {
+            "ssml": "Start of Content"
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/list-html-native/utterances.json b/fixtures/list-html-native/utterances.json
index 5e68b82..0c61a07 100644
--- a/fixtures/list-html-native/utterances.json
+++ b/fixtures/list-html-native/utterances.json
@@ -1,11 +1,28 @@
-[
-  {
-    "plain": "First item"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "First item"
+      },
+      {
+        "plain": "Second item"
+      },
+      {
+        "plain": "Third item"
+      }
+    ]
   },
-  {
-    "plain": "Second item"
-  },
-  {
-    "plain": "Third item"
+  "ssml": {
+    "base": [
+      {
+        "ssml": "First item"
+      },
+      {
+        "ssml": "Second item"
+      },
+      {
+        "ssml": "Third item"
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/list-role-aria/utterances.json b/fixtures/list-role-aria/utterances.json
index 5e68b82..0c61a07 100644
--- a/fixtures/list-role-aria/utterances.json
+++ b/fixtures/list-role-aria/utterances.json
@@ -1,11 +1,28 @@
-[
-  {
-    "plain": "First item"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "First item"
+      },
+      {
+        "plain": "Second item"
+      },
+      {
+        "plain": "Third item"
+      }
+    ]
   },
-  {
-    "plain": "Second item"
-  },
-  {
-    "plain": "Third item"
+  "ssml": {
+    "base": [
+      {
+        "ssml": "First item"
+      },
+      {
+        "ssml": "Second item"
+      },
+      {
+        "ssml": "Third item"
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/loa-epub-type/gnd.json b/fixtures/loa-epub-type/gnd.json
index a15c98f..c920e2b 100644
--- a/fixtures/loa-epub-type/gnd.json
+++ b/fixtures/loa-epub-type/gnd.json
@@ -1,27 +1,34 @@
 {
   "role": [
-    "navigation",
-    "loa"
+    "body"
   ],
   "children": [
     {
       "role": [
-        "list"
+        "navigation",
+        "loa"
       ],
       "children": [
         {
           "role": [
-            "listItem"
+            "list"
           ],
-          "text": "Audio 1. Foghorn recording",
-          "textref": "chapter1.xhtml#audio1"
-        },
-        {
-          "role": [
-            "listItem"
-          ],
-          "text": "Audio 2. Keeper's log reading",
-          "textref": "chapter2.xhtml#audio2"
+          "children": [
+            {
+              "textref": "chapter1.xhtml#audio1",
+              "text": "Audio 1. Foghorn recording",
+              "role": [
+                "listItem"
+              ]
+            },
+            {
+              "textref": "chapter2.xhtml#audio2",
+              "text": "Audio 2. Keeper's log reading",
+              "role": [
+                "listItem"
+              ]
+            }
+          ]
         }
       ]
     }
diff --git a/fixtures/loa-epub-type/input.html b/fixtures/loa-epub-type/input.xhtml
similarity index 100%
rename from fixtures/loa-epub-type/input.html
rename to fixtures/loa-epub-type/input.xhtml
diff --git a/fixtures/loa-epub-type/utterances.json b/fixtures/loa-epub-type/utterances.json
index 67732e5..fe45b40 100644
--- a/fixtures/loa-epub-type/utterances.json
+++ b/fixtures/loa-epub-type/utterances.json
@@ -1,8 +1,80 @@
-[
-  {
-    "plain": "Audio 1. Foghorn recording"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the list of audio clips."
+      },
+      {
+        "plain": "Audio 1. Foghorn recording"
+      },
+      {
+        "plain": "Audio 2. Keeper's log reading"
+      },
+      {
+        "plain": "End of the list of audio clips."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "skip": [
+            "loa"
+          ]
+        },
+        "utterances": []
+      },
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "Audio 1. Foghorn recording"
+          },
+          {
+            "plain": "Audio 2. Keeper's log reading"
+          }
+        ]
+      }
+    ]
   },
-  {
-    "plain": "Audio 2. Keeper's log reading"
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the list of audio clips."
+      },
+      {
+        "ssml": "Audio 1. Foghorn recording"
+      },
+      {
+        "ssml": "Audio 2. Keeper's log reading"
+      },
+      {
+        "ssml": "End of the list of audio clips."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "skip": [
+            "loa"
+          ]
+        },
+        "utterances": []
+      },
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "Audio 1. Foghorn recording"
+          },
+          {
+            "ssml": "Audio 2. Keeper's log reading"
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/loi-epub-type/gnd.json b/fixtures/loi-epub-type/gnd.json
index c75c0f8..bcc3d35 100644
--- a/fixtures/loi-epub-type/gnd.json
+++ b/fixtures/loi-epub-type/gnd.json
@@ -1,27 +1,34 @@
 {
   "role": [
-    "navigation",
-    "loi"
+    "body"
   ],
   "children": [
     {
       "role": [
-        "list"
+        "navigation",
+        "loi"
       ],
       "children": [
         {
           "role": [
-            "listItem"
+            "list"
           ],
-          "text": "Figure 1. Lighthouse cross-section",
-          "textref": "chapter1.xhtml#fig1"
-        },
-        {
-          "role": [
-            "listItem"
-          ],
-          "text": "Figure 2. Fresnel lens diagram",
-          "textref": "chapter2.xhtml#fig2"
+          "children": [
+            {
+              "textref": "chapter1.xhtml#fig1",
+              "text": "Figure 1. Lighthouse cross-section",
+              "role": [
+                "listItem"
+              ]
+            },
+            {
+              "textref": "chapter2.xhtml#fig2",
+              "text": "Figure 2. Fresnel lens diagram",
+              "role": [
+                "listItem"
+              ]
+            }
+          ]
         }
       ]
     }
diff --git a/fixtures/loi-epub-type/input.html b/fixtures/loi-epub-type/input.xhtml
similarity index 100%
rename from fixtures/loi-epub-type/input.html
rename to fixtures/loi-epub-type/input.xhtml
diff --git a/fixtures/loi-epub-type/utterances.json b/fixtures/loi-epub-type/utterances.json
index ab995b1..31a6b0f 100644
--- a/fixtures/loi-epub-type/utterances.json
+++ b/fixtures/loi-epub-type/utterances.json
@@ -1,8 +1,80 @@
-[
-  {
-    "plain": "Figure 1. Lighthouse cross-section"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the list of illustrations."
+      },
+      {
+        "plain": "Figure 1. Lighthouse cross-section"
+      },
+      {
+        "plain": "Figure 2. Fresnel lens diagram"
+      },
+      {
+        "plain": "End of the list of illustrations."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "skip": [
+            "loi"
+          ]
+        },
+        "utterances": []
+      },
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "Figure 1. Lighthouse cross-section"
+          },
+          {
+            "plain": "Figure 2. Fresnel lens diagram"
+          }
+        ]
+      }
+    ]
   },
-  {
-    "plain": "Figure 2. Fresnel lens diagram"
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the list of illustrations."
+      },
+      {
+        "ssml": "Figure 1. Lighthouse cross-section"
+      },
+      {
+        "ssml": "Figure 2. Fresnel lens diagram"
+      },
+      {
+        "ssml": "End of the list of illustrations."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "skip": [
+            "loi"
+          ]
+        },
+        "utterances": []
+      },
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "Figure 1. Lighthouse cross-section"
+          },
+          {
+            "ssml": "Figure 2. Fresnel lens diagram"
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/lot-epub-type/gnd.json b/fixtures/lot-epub-type/gnd.json
index 9737664..755090b 100644
--- a/fixtures/lot-epub-type/gnd.json
+++ b/fixtures/lot-epub-type/gnd.json
@@ -1,27 +1,34 @@
 {
   "role": [
-    "navigation",
-    "lot"
+    "body"
   ],
   "children": [
     {
       "role": [
-        "list"
+        "navigation",
+        "lot"
       ],
       "children": [
         {
           "role": [
-            "listItem"
+            "list"
           ],
-          "text": "Table 1. Lighthouse construction dates",
-          "textref": "appendix.xhtml#table1"
-        },
-        {
-          "role": [
-            "listItem"
-          ],
-          "text": "Table 2. Keeper staffing by decade",
-          "textref": "appendix.xhtml#table2"
+          "children": [
+            {
+              "textref": "appendix.xhtml#table1",
+              "text": "Table 1. Lighthouse construction dates",
+              "role": [
+                "listItem"
+              ]
+            },
+            {
+              "textref": "appendix.xhtml#table2",
+              "text": "Table 2. Keeper staffing by decade",
+              "role": [
+                "listItem"
+              ]
+            }
+          ]
         }
       ]
     }
diff --git a/fixtures/lot-epub-type/input.html b/fixtures/lot-epub-type/input.xhtml
similarity index 100%
rename from fixtures/lot-epub-type/input.html
rename to fixtures/lot-epub-type/input.xhtml
diff --git a/fixtures/lot-epub-type/utterances.json b/fixtures/lot-epub-type/utterances.json
index 8b8a724..853f7e6 100644
--- a/fixtures/lot-epub-type/utterances.json
+++ b/fixtures/lot-epub-type/utterances.json
@@ -1,8 +1,80 @@
-[
-  {
-    "plain": "Table 1. Lighthouse construction dates"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the list of tables."
+      },
+      {
+        "plain": "Table 1. Lighthouse construction dates"
+      },
+      {
+        "plain": "Table 2. Keeper staffing by decade"
+      },
+      {
+        "plain": "End of the list of tables."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "skip": [
+            "lot"
+          ]
+        },
+        "utterances": []
+      },
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "Table 1. Lighthouse construction dates"
+          },
+          {
+            "plain": "Table 2. Keeper staffing by decade"
+          }
+        ]
+      }
+    ]
   },
-  {
-    "plain": "Table 2. Keeper staffing by decade"
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the list of tables."
+      },
+      {
+        "ssml": "Table 1. Lighthouse construction dates"
+      },
+      {
+        "ssml": "Table 2. Keeper staffing by decade"
+      },
+      {
+        "ssml": "End of the list of tables."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "skip": [
+            "lot"
+          ]
+        },
+        "utterances": []
+      },
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "Table 1. Lighthouse construction dates"
+          },
+          {
+            "ssml": "Table 2. Keeper staffing by decade"
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/lov-epub-type/gnd.json b/fixtures/lov-epub-type/gnd.json
index 2206a61..d58a97c 100644
--- a/fixtures/lov-epub-type/gnd.json
+++ b/fixtures/lov-epub-type/gnd.json
@@ -1,27 +1,34 @@
 {
   "role": [
-    "navigation",
-    "lov"
+    "body"
   ],
   "children": [
     {
       "role": [
-        "list"
+        "navigation",
+        "lov"
       ],
       "children": [
         {
           "role": [
-            "listItem"
+            "list"
           ],
-          "text": "Video 1. Lamp mechanism in motion",
-          "textref": "chapter1.xhtml#video1"
-        },
-        {
-          "role": [
-            "listItem"
-          ],
-          "text": "Video 2. Automation retrofit",
-          "textref": "chapter3.xhtml#video2"
+          "children": [
+            {
+              "textref": "chapter1.xhtml#video1",
+              "text": "Video 1. Lamp mechanism in motion",
+              "role": [
+                "listItem"
+              ]
+            },
+            {
+              "textref": "chapter3.xhtml#video2",
+              "text": "Video 2. Automation retrofit",
+              "role": [
+                "listItem"
+              ]
+            }
+          ]
         }
       ]
     }
diff --git a/fixtures/lov-epub-type/input.html b/fixtures/lov-epub-type/input.xhtml
similarity index 100%
rename from fixtures/lov-epub-type/input.html
rename to fixtures/lov-epub-type/input.xhtml
diff --git a/fixtures/lov-epub-type/utterances.json b/fixtures/lov-epub-type/utterances.json
index a4f9cb2..96350e6 100644
--- a/fixtures/lov-epub-type/utterances.json
+++ b/fixtures/lov-epub-type/utterances.json
@@ -1,8 +1,80 @@
-[
-  {
-    "plain": "Video 1. Lamp mechanism in motion"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the list of video clips."
+      },
+      {
+        "plain": "Video 1. Lamp mechanism in motion"
+      },
+      {
+        "plain": "Video 2. Automation retrofit"
+      },
+      {
+        "plain": "End of the list of video clips."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "skip": [
+            "lov"
+          ]
+        },
+        "utterances": []
+      },
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "Video 1. Lamp mechanism in motion"
+          },
+          {
+            "plain": "Video 2. Automation retrofit"
+          }
+        ]
+      }
+    ]
   },
-  {
-    "plain": "Video 2. Automation retrofit"
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the list of video clips."
+      },
+      {
+        "ssml": "Video 1. Lamp mechanism in motion"
+      },
+      {
+        "ssml": "Video 2. Automation retrofit"
+      },
+      {
+        "ssml": "End of the list of video clips."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "skip": [
+            "lov"
+          ]
+        },
+        "utterances": []
+      },
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "Video 1. Lamp mechanism in motion"
+          },
+          {
+            "ssml": "Video 2. Automation retrofit"
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/main-html-native/utterances.json b/fixtures/main-html-native/utterances.json
index 432fd08..98cf81c 100644
--- a/fixtures/main-html-native/utterances.json
+++ b/fixtures/main-html-native/utterances.json
@@ -1,5 +1,16 @@
-[
-  {
-    "plain": "The central topic of this document."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "The central topic of this document."
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "The central topic of this document."
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/main-role-aria/utterances.json b/fixtures/main-role-aria/utterances.json
index 432fd08..98cf81c 100644
--- a/fixtures/main-role-aria/utterances.json
+++ b/fixtures/main-role-aria/utterances.json
@@ -1,5 +1,16 @@
-[
-  {
-    "plain": "The central topic of this document."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "The central topic of this document."
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "The central topic of this document."
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/manifest.json b/fixtures/manifest.json
index c279861..851dc2e 100644
--- a/fixtures/manifest.json
+++ b/fixtures/manifest.json
@@ -5,7 +5,7 @@
     "role": "abstract",
     "description": "abstract role via epub:type=\"abstract\"",
     "files": {
-      "input": "input.html",
+      "input": "input.xhtml",
       "gnd": "gnd.json",
       "utterances": "utterances.json"
     }
@@ -27,7 +27,7 @@
     "role": "acknowledgments",
     "description": "acknowledgments role via epub:type=\"acknowledgments\"",
     "files": {
-      "input": "input.html",
+      "input": "input.xhtml",
       "gnd": "gnd.json",
       "utterances": "utterances.json"
     }
@@ -49,7 +49,7 @@
     "role": "afterword",
     "description": "afterword role via epub:type=\"afterword\"",
     "files": {
-      "input": "input.html",
+      "input": "input.xhtml",
       "gnd": "gnd.json",
       "utterances": "utterances.json"
     }
@@ -71,7 +71,7 @@
     "role": "appendix",
     "description": "appendix role via epub:type=\"appendix\" on a <section>",
     "files": {
-      "input": "input.html",
+      "input": "input.xhtml",
       "gnd": "gnd.json",
       "utterances": "utterances.json"
     }
@@ -106,12 +106,8 @@
     "files": {
       "input": "input.html",
       "gnd": "gnd.json",
-      "utterances": "utterances.json",
-      "utterancesSkipped": "utterances-skipped.json"
-    },
-    "skip": [
-      "aside"
-    ]
+      "utterances": "utterances.json"
+    }
   },
   {
     "id": "audio-html-native",
@@ -130,7 +126,7 @@
     "role": "backlink",
     "description": "backlink role via epub:type=\"backlink\" on an <a href>",
     "files": {
-      "input": "input.html",
+      "input": "input.xhtml",
       "gnd": "gnd.json",
       "utterances": "utterances.json"
     }
@@ -152,7 +148,7 @@
     "role": "bibliography",
     "description": "A bibliography list of cited references, via epub:type=\"bibliography\" on a <section>",
     "files": {
-      "input": "input.html",
+      "input": "input.xhtml",
       "gnd": "gnd.json",
       "utterances": "utterances.json"
     }
@@ -174,7 +170,7 @@
     "role": "biblioref",
     "description": "biblioref role via epub:type=\"biblioref\" on an <a href>",
     "files": {
-      "input": "input.html",
+      "input": "input.xhtml",
       "gnd": "gnd.json",
       "utterances": "utterances.json"
     }
@@ -218,7 +214,7 @@
     "role": "chapter",
     "description": "chapter role via epub:type=\"chapter\", containing a heading",
     "files": {
-      "input": "input.html",
+      "input": "input.xhtml",
       "gnd": "gnd.json",
       "utterances": "utterances.json"
     }
@@ -240,7 +236,7 @@
     "role": "colophon",
     "description": "colophon role via epub:type=\"colophon\"",
     "files": {
-      "input": "input.html",
+      "input": "input.xhtml",
       "gnd": "gnd.json",
       "utterances": "utterances.json"
     }
@@ -273,7 +269,7 @@
     "role": "conclusion",
     "description": "conclusion role via epub:type=\"conclusion\"",
     "files": {
-      "input": "input.html",
+      "input": "input.xhtml",
       "gnd": "gnd.json",
       "utterances": "utterances.json"
     }
@@ -295,7 +291,7 @@
     "role": "cover",
     "description": "cover role via epub:type=\"cover\" on a <section> wrapping the cover image",
     "files": {
-      "input": "input.html",
+      "input": "input.xhtml",
       "gnd": "gnd.json",
       "utterances": "utterances.json"
     }
@@ -317,7 +313,7 @@
     "role": "credit",
     "description": "credit role via epub:type=\"credit\" on a <span>",
     "files": {
-      "input": "input.html",
+      "input": "input.xhtml",
       "gnd": "gnd.json",
       "utterances": "utterances.json"
     }
@@ -339,7 +335,7 @@
     "role": "credits",
     "description": "A collection of credits, via epub:type=\"credits\"; each entry is a <span epub:type=\"credit\">",
     "files": {
-      "input": "input.html",
+      "input": "input.xhtml",
       "gnd": "gnd.json",
       "utterances": "utterances.json"
     }
@@ -361,7 +357,7 @@
     "role": "dedication",
     "description": "dedication role via epub:type=\"dedication\"",
     "files": {
-      "input": "input.html",
+      "input": "input.xhtml",
       "gnd": "gnd.json",
       "utterances": "utterances.json"
     }
@@ -383,7 +379,7 @@
     "role": "definition",
     "description": "definition role via epub:type=\"glossdef\" on a <dd>, nested in a <dl epub:type=\"glossary\">",
     "files": {
-      "input": "input.html",
+      "input": "input.xhtml",
       "gnd": "gnd.json",
       "utterances": "utterances.json"
     }
@@ -427,7 +423,7 @@
     "role": "endnotes",
     "description": "A collection of endnotes, via epub:type=\"endnotes\" on a <section>; each entry is an <aside epub:type=\"footnote\">",
     "files": {
-      "input": "input.html",
+      "input": "input.xhtml",
       "gnd": "gnd.json",
       "utterances": "utterances.json"
     }
@@ -449,7 +445,7 @@
     "role": "epigraph",
     "description": "epigraph role via epub:type=\"epigraph\"",
     "files": {
-      "input": "input.html",
+      "input": "input.xhtml",
       "gnd": "gnd.json",
       "utterances": "utterances.json"
     }
@@ -471,7 +467,7 @@
     "role": "epilogue",
     "description": "epilogue role via epub:type=\"epilogue\"",
     "files": {
-      "input": "input.html",
+      "input": "input.xhtml",
       "gnd": "gnd.json",
       "utterances": "utterances.json"
     }
@@ -493,7 +489,7 @@
     "role": "errata",
     "description": "errata role via epub:type=\"errata\"",
     "files": {
-      "input": "input.html",
+      "input": "input.xhtml",
       "gnd": "gnd.json",
       "utterances": "utterances.json"
     }
@@ -515,7 +511,7 @@
     "role": "example",
     "description": "example role via epub:type=\"example\"",
     "files": {
-      "input": "input.html",
+      "input": "input.xhtml",
       "gnd": "gnd.json",
       "utterances": "utterances.json"
     }
@@ -537,7 +533,7 @@
     "role": "figure",
     "description": "A figure containing an image, with no caption, via epub:type=\"figure\"",
     "files": {
-      "input": "input.html",
+      "input": "input.xhtml",
       "gnd": "gnd.json",
       "utterances": "utterances.json"
     }
@@ -603,14 +599,10 @@
     "role": "footnote",
     "description": "A paragraph with one footnote reference and its footnote content, via epub:type",
     "files": {
-      "input": "input.html",
+      "input": "input.xhtml",
       "gnd": "gnd.json",
-      "utterances": "utterances.json",
-      "utterancesSkipped": "utterances-skipped.json"
-    },
-    "skip": [
-      "footnote"
-    ]
+      "utterances": "utterances.json"
+    }
   },
   {
     "id": "footnote-role-aria",
@@ -620,12 +612,8 @@
     "files": {
       "input": "input.html",
       "gnd": "gnd.json",
-      "utterances": "utterances.json",
-      "utterancesSkipped": "utterances-skipped.json"
-    },
-    "skip": [
-      "footnote"
-    ]
+      "utterances": "utterances.json"
+    }
   },
   {
     "id": "foreword-epub-type",
@@ -633,7 +621,7 @@
     "role": "foreword",
     "description": "foreword role via epub:type=\"foreword\"",
     "files": {
-      "input": "input.html",
+      "input": "input.xhtml",
       "gnd": "gnd.json",
       "utterances": "utterances.json"
     }
@@ -655,7 +643,7 @@
     "role": "glossary",
     "description": "A glossary of term/definition entries via epub:type=\"glossary\" on a <dl>, with term/definition as its directly owned elements",
     "files": {
-      "input": "input.html",
+      "input": "input.xhtml",
       "gnd": "gnd.json",
       "utterances": "utterances.json"
     }
@@ -677,7 +665,7 @@
     "role": "glossref",
     "description": "glossref role via epub:type=\"glossref\" on an <a href>",
     "files": {
-      "input": "input.html",
+      "input": "input.xhtml",
       "gnd": "gnd.json",
       "utterances": "utterances.json"
     }
@@ -776,7 +764,7 @@
     "role": "index",
     "description": "An index navigation list, containing links to key subjects and names, via epub:type",
     "files": {
-      "input": "input.html",
+      "input": "input.xhtml",
       "gnd": "gnd.json",
       "utterances": "utterances.json"
     }
@@ -798,7 +786,7 @@
     "role": "introduction",
     "description": "introduction role via epub:type=\"introduction\"",
     "files": {
-      "input": "input.html",
+      "input": "input.xhtml",
       "gnd": "gnd.json",
       "utterances": "utterances.json"
     }
@@ -820,7 +808,7 @@
     "role": "landmarks",
     "description": "A landmarks navigation list, containing links to the cover, table of contents, and start of content",
     "files": {
-      "input": "input.html",
+      "input": "input.xhtml",
       "gnd": "gnd.json",
       "utterances": "utterances.json"
     }
@@ -853,7 +841,7 @@
     "role": "loa",
     "description": "A list-of-audio-clips navigation list, containing links to audio clips in the work",
     "files": {
-      "input": "input.html",
+      "input": "input.xhtml",
       "gnd": "gnd.json",
       "utterances": "utterances.json"
     }
@@ -864,7 +852,7 @@
     "role": "loi",
     "description": "A list-of-illustrations navigation list, containing links to illustrations in the work",
     "files": {
-      "input": "input.html",
+      "input": "input.xhtml",
       "gnd": "gnd.json",
       "utterances": "utterances.json"
     }
@@ -875,7 +863,7 @@
     "role": "lot",
     "description": "A list-of-tables navigation list, containing links to tables in the work",
     "files": {
-      "input": "input.html",
+      "input": "input.xhtml",
       "gnd": "gnd.json",
       "utterances": "utterances.json"
     }
@@ -886,7 +874,7 @@
     "role": "lov",
     "description": "A list-of-video-clips navigation list, containing links to video clips in the work",
     "files": {
-      "input": "input.html",
+      "input": "input.xhtml",
       "gnd": "gnd.json",
       "utterances": "utterances.json"
     }
@@ -963,7 +951,7 @@
     "role": "notice",
     "description": "notice role via epub:type=\"notice\"",
     "files": {
-      "input": "input.html",
+      "input": "input.xhtml",
       "gnd": "gnd.json",
       "utterances": "utterances.json"
     }
@@ -985,14 +973,10 @@
     "role": "pagebreak",
     "description": "A standalone pagebreak and one falling in the middle of a sentence, via epub:type=\"pagebreak\"",
     "files": {
-      "input": "input.html",
+      "input": "input.xhtml",
       "gnd": "gnd.json",
-      "utterances": "utterances.json",
-      "utterancesSkipped": "utterances-skipped.json"
-    },
-    "skip": [
-      "pagebreak"
-    ]
+      "utterances": "utterances.json"
+    }
   },
   {
     "id": "pagebreak-role-aria",
@@ -1002,12 +986,8 @@
     "files": {
       "input": "input.html",
       "gnd": "gnd.json",
-      "utterances": "utterances.json",
-      "utterancesSkipped": "utterances-skipped.json"
-    },
-    "skip": [
-      "pagebreak"
-    ]
+      "utterances": "utterances.json"
+    }
   },
   {
     "id": "pagelist-epub-type",
@@ -1015,7 +995,7 @@
     "role": "pagelist",
     "description": "A page-list navigation list, containing links to pagebreaks, via epub:type",
     "files": {
-      "input": "input.html",
+      "input": "input.xhtml",
       "gnd": "gnd.json",
       "utterances": "utterances.json"
     }
@@ -1125,7 +1105,7 @@
     "role": "part",
     "description": "part role via epub:type=\"part\", containing a heading",
     "files": {
-      "input": "input.html",
+      "input": "input.xhtml",
       "gnd": "gnd.json",
       "utterances": "utterances.json"
     }
@@ -1147,7 +1127,7 @@
     "role": "preface",
     "description": "preface role via epub:type=\"preface\"",
     "files": {
-      "input": "input.html",
+      "input": "input.xhtml",
       "gnd": "gnd.json",
       "utterances": "utterances.json"
     }
@@ -1191,7 +1171,7 @@
     "role": "prologue",
     "description": "prologue role via epub:type=\"prologue\"",
     "files": {
-      "input": "input.html",
+      "input": "input.xhtml",
       "gnd": "gnd.json",
       "utterances": "utterances.json"
     }
@@ -1213,7 +1193,7 @@
     "role": "pullquote",
     "description": "pullquote role via epub:type=\"pullquote\" on an <aside>",
     "files": {
-      "input": "input.html",
+      "input": "input.xhtml",
       "gnd": "gnd.json",
       "utterances": "utterances.json"
     }
@@ -1235,7 +1215,7 @@
     "role": "qna",
     "description": "qna role via epub:type=\"qna\" on a <section>",
     "files": {
-      "input": "input.html",
+      "input": "input.xhtml",
       "gnd": "gnd.json",
       "utterances": "utterances.json"
     }
@@ -1301,7 +1281,7 @@
     "role": "subtitle",
     "description": "subtitle role via epub:type=\"subtitle\"",
     "files": {
-      "input": "input.html",
+      "input": "input.xhtml",
       "gnd": "gnd.json",
       "utterances": "utterances.json"
     }
@@ -1356,7 +1336,7 @@
     "role": "term",
     "description": "term role via epub:type=\"glossterm\" on a <dt>, nested in a <dl epub:type=\"glossary\">",
     "files": {
-      "input": "input.html",
+      "input": "input.xhtml",
       "gnd": "gnd.json",
       "utterances": "utterances.json"
     }
@@ -1389,7 +1369,7 @@
     "role": "tip",
     "description": "tip role via epub:type=\"tip\" on an <aside>",
     "files": {
-      "input": "input.html",
+      "input": "input.xhtml",
       "gnd": "gnd.json",
       "utterances": "utterances.json"
     }
@@ -1411,7 +1391,7 @@
     "role": "toc",
     "description": "A table-of-contents navigation list, containing links to sectional headings, via epub:type",
     "files": {
-      "input": "input.html",
+      "input": "input.xhtml",
       "gnd": "gnd.json",
       "utterances": "utterances.json"
     }
diff --git a/fixtures/math-html-native/utterances.json b/fixtures/math-html-native/utterances.json
index 27bacc9..cbacce7 100644
--- a/fixtures/math-html-native/utterances.json
+++ b/fixtures/math-html-native/utterances.json
@@ -1,5 +1,16 @@
-[
-  {
-    "plain": "x squared plus y squared equals z squared"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "x squared plus y squared equals z squared"
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "x squared plus y squared equals z squared"
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/math-role-aria/utterances.json b/fixtures/math-role-aria/utterances.json
index 27bacc9..cbacce7 100644
--- a/fixtures/math-role-aria/utterances.json
+++ b/fixtures/math-role-aria/utterances.json
@@ -1,5 +1,16 @@
-[
-  {
-    "plain": "x squared plus y squared equals z squared"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "x squared plus y squared equals z squared"
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "x squared plus y squared equals z squared"
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/navigation-html-native/utterances.json b/fixtures/navigation-html-native/utterances.json
index 3ca8354..6024740 100644
--- a/fixtures/navigation-html-native/utterances.json
+++ b/fixtures/navigation-html-native/utterances.json
@@ -1,5 +1,16 @@
-[
-  {
-    "plain": "Link to the next chapter."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Link to the next chapter."
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Link to the next chapter."
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/navigation-role-aria/utterances.json b/fixtures/navigation-role-aria/utterances.json
index 3ca8354..6024740 100644
--- a/fixtures/navigation-role-aria/utterances.json
+++ b/fixtures/navigation-role-aria/utterances.json
@@ -1,5 +1,16 @@
-[
-  {
-    "plain": "Link to the next chapter."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Link to the next chapter."
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Link to the next chapter."
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/notice-epub-type/gnd.json b/fixtures/notice-epub-type/gnd.json
index 1a36593..9485705 100644
--- a/fixtures/notice-epub-type/gnd.json
+++ b/fixtures/notice-epub-type/gnd.json
@@ -1,6 +1,13 @@
 {
   "role": [
-    "notice"
+    "body"
   ],
-  "text": "Caution: the tower stairs are uneven."
+  "children": [
+    {
+      "text": "Caution: the tower stairs are uneven.",
+      "role": [
+        "notice"
+      ]
+    }
+  ]
 }
diff --git a/fixtures/notice-epub-type/input.html b/fixtures/notice-epub-type/input.xhtml
similarity index 100%
rename from fixtures/notice-epub-type/input.html
rename to fixtures/notice-epub-type/input.xhtml
diff --git a/fixtures/notice-epub-type/utterances.json b/fixtures/notice-epub-type/utterances.json
index 62cb367..b15eb71 100644
--- a/fixtures/notice-epub-type/utterances.json
+++ b/fixtures/notice-epub-type/utterances.json
@@ -1,5 +1,46 @@
-[
-  {
-    "plain": "Caution: the tower stairs are uneven."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Notice."
+      },
+      {
+        "plain": "Caution: the tower stairs are uneven."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "Caution: the tower stairs are uneven."
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Notice."
+      },
+      {
+        "ssml": "Caution: the tower stairs are uneven."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "Caution: the tower stairs are uneven."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/notice-role-aria/utterances.json b/fixtures/notice-role-aria/utterances.json
index 62cb367..b15eb71 100644
--- a/fixtures/notice-role-aria/utterances.json
+++ b/fixtures/notice-role-aria/utterances.json
@@ -1,5 +1,46 @@
-[
-  {
-    "plain": "Caution: the tower stairs are uneven."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Notice."
+      },
+      {
+        "plain": "Caution: the tower stairs are uneven."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "Caution: the tower stairs are uneven."
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Notice."
+      },
+      {
+        "ssml": "Caution: the tower stairs are uneven."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "Caution: the tower stairs are uneven."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/pagebreak-epub-type/gnd.json b/fixtures/pagebreak-epub-type/gnd.json
index 22150a2..5dc9ae0 100644
--- a/fixtures/pagebreak-epub-type/gnd.json
+++ b/fixtures/pagebreak-epub-type/gnd.json
@@ -1,27 +1,30 @@
 {
+  "role": [
+    "body"
+  ],
   "children": [
     {
+      "text": "4",
       "role": [
         "pagebreak"
-      ],
-      "text": "4"
+      ]
     },
     {
-      "role": [
-        "paragraph"
-      ],
       "text": {
+        "language": "en",
         "plain": "And the next pagebreak is in the middle of a sentence.",
-        "ssml": "And the next pagebreak is in the middle <readium:pagebreak id=\"pagebreak1\" /> of a sentence.",
-        "language": "en"
+        "ssml": "And the next pagebreak is in the middle <readium:pagebreak id=\"pagebreak1\" /> of a sentence."
       },
+      "role": [
+        "paragraph"
+      ],
       "children": [
         {
+          "id": "pagebreak1",
+          "text": "5",
           "role": [
             "pagebreak"
-          ],
-          "id": "pagebreak1",
-          "text": "5"
+          ]
         }
       ]
     }
diff --git a/fixtures/pagebreak-epub-type/input.html b/fixtures/pagebreak-epub-type/input.xhtml
similarity index 100%
rename from fixtures/pagebreak-epub-type/input.html
rename to fixtures/pagebreak-epub-type/input.xhtml
diff --git a/fixtures/pagebreak-epub-type/meta.json b/fixtures/pagebreak-epub-type/meta.json
index 4428864..bdf0f44 100644
--- a/fixtures/pagebreak-epub-type/meta.json
+++ b/fixtures/pagebreak-epub-type/meta.json
@@ -6,6 +6,5 @@
     "pagebreak"
   ],
   "sourceRef": "https://github.com/readium/guided-navigation/tree/main/examples/read-aloud",
-  "inputKind": "document",
-  "skip": ["pagebreak"]
+  "inputKind": "document"
 }
diff --git a/fixtures/pagebreak-epub-type/utterances-skipped.json b/fixtures/pagebreak-epub-type/utterances-skipped.json
deleted file mode 100644
index b81f5fc..0000000
--- a/fixtures/pagebreak-epub-type/utterances-skipped.json
+++ /dev/null
@@ -1,6 +0,0 @@
-[
-  {
-    "plain": "And the next pagebreak is in the middle of a sentence.",
-    "language": "en"
-  }
-]
diff --git a/fixtures/pagebreak-epub-type/utterances.json b/fixtures/pagebreak-epub-type/utterances.json
index eb8dc68..0f023a0 100644
--- a/fixtures/pagebreak-epub-type/utterances.json
+++ b/fixtures/pagebreak-epub-type/utterances.json
@@ -1,18 +1,160 @@
-[
-  {
-    "plain": "Pagebreak."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Pagebreak."
+      },
+      {
+        "plain": "4"
+      },
+      {
+        "language": "en",
+        "plain": "And the next pagebreak is in the middle of a sentence."
+      },
+      {
+        "plain": "Pagebreak."
+      },
+      {
+        "plain": "5"
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "skip": [
+            "pagebreak"
+          ]
+        },
+        "utterances": [
+          {
+            "language": "en",
+            "plain": "And the next pagebreak is in the middle of a sentence."
+          }
+        ]
+      },
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "4"
+          },
+          {
+            "language": "en",
+            "plain": "And the next pagebreak is in the middle of a sentence."
+          },
+          {
+            "plain": "5"
+          }
+        ]
+      },
+      {
+        "options": {
+          "interruptSentence": true
+        },
+        "utterances": [
+          {
+            "plain": "Pagebreak."
+          },
+          {
+            "plain": "4"
+          },
+          {
+            "language": "en",
+            "plain": "And the next pagebreak is in the middle"
+          },
+          {
+            "plain": "Pagebreak."
+          },
+          {
+            "plain": "5"
+          },
+          {
+            "language": "en",
+            "plain": "of a sentence."
+          }
+        ]
+      }
+    ]
   },
-  {
-    "plain": "4"
-  },
-  {
-    "plain": "And the next pagebreak is in the middle of a sentence.",
-    "language": "en"
-  },
-  {
-    "plain": "Pagebreak."
-  },
-  {
-    "plain": "5"
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Pagebreak."
+      },
+      {
+        "ssml": "4"
+      },
+      {
+        "language": "en",
+        "ssml": "And the next pagebreak is in the middle of a sentence."
+      },
+      {
+        "ssml": "Pagebreak."
+      },
+      {
+        "ssml": "5"
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "skip": [
+            "pagebreak"
+          ]
+        },
+        "utterances": [
+          {
+            "language": "en",
+            "ssml": "And the next pagebreak is in the middle of a sentence."
+          }
+        ]
+      },
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "4"
+          },
+          {
+            "language": "en",
+            "ssml": "And the next pagebreak is in the middle of a sentence."
+          },
+          {
+            "ssml": "5"
+          }
+        ]
+      },
+      {
+        "options": {
+          "interruptSentence": true
+        },
+        "utterances": [
+          {
+            "ssml": "Pagebreak."
+          },
+          {
+            "ssml": "4"
+          },
+          {
+            "language": "en",
+            "ssml": "And the next pagebreak is in the middle"
+          },
+          {
+            "ssml": "Pagebreak."
+          },
+          {
+            "ssml": "5"
+          },
+          {
+            "language": "en",
+            "ssml": "of a sentence."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/pagebreak-role-aria/meta.json b/fixtures/pagebreak-role-aria/meta.json
index 7599327..c31359f 100644
--- a/fixtures/pagebreak-role-aria/meta.json
+++ b/fixtures/pagebreak-role-aria/meta.json
@@ -6,6 +6,5 @@
     "pagebreak"
   ],
   "sourceRef": "https://github.com/readium/guided-navigation/tree/main/examples/read-aloud",
-  "inputKind": "fragment",
-  "skip": ["pagebreak"]
+  "inputKind": "fragment"
 }
diff --git a/fixtures/pagebreak-role-aria/utterances-skipped.json b/fixtures/pagebreak-role-aria/utterances-skipped.json
deleted file mode 100644
index b81f5fc..0000000
--- a/fixtures/pagebreak-role-aria/utterances-skipped.json
+++ /dev/null
@@ -1,6 +0,0 @@
-[
-  {
-    "plain": "And the next pagebreak is in the middle of a sentence.",
-    "language": "en"
-  }
-]
diff --git a/fixtures/pagebreak-role-aria/utterances.json b/fixtures/pagebreak-role-aria/utterances.json
index eb8dc68..0f023a0 100644
--- a/fixtures/pagebreak-role-aria/utterances.json
+++ b/fixtures/pagebreak-role-aria/utterances.json
@@ -1,18 +1,160 @@
-[
-  {
-    "plain": "Pagebreak."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Pagebreak."
+      },
+      {
+        "plain": "4"
+      },
+      {
+        "language": "en",
+        "plain": "And the next pagebreak is in the middle of a sentence."
+      },
+      {
+        "plain": "Pagebreak."
+      },
+      {
+        "plain": "5"
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "skip": [
+            "pagebreak"
+          ]
+        },
+        "utterances": [
+          {
+            "language": "en",
+            "plain": "And the next pagebreak is in the middle of a sentence."
+          }
+        ]
+      },
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "4"
+          },
+          {
+            "language": "en",
+            "plain": "And the next pagebreak is in the middle of a sentence."
+          },
+          {
+            "plain": "5"
+          }
+        ]
+      },
+      {
+        "options": {
+          "interruptSentence": true
+        },
+        "utterances": [
+          {
+            "plain": "Pagebreak."
+          },
+          {
+            "plain": "4"
+          },
+          {
+            "language": "en",
+            "plain": "And the next pagebreak is in the middle"
+          },
+          {
+            "plain": "Pagebreak."
+          },
+          {
+            "plain": "5"
+          },
+          {
+            "language": "en",
+            "plain": "of a sentence."
+          }
+        ]
+      }
+    ]
   },
-  {
-    "plain": "4"
-  },
-  {
-    "plain": "And the next pagebreak is in the middle of a sentence.",
-    "language": "en"
-  },
-  {
-    "plain": "Pagebreak."
-  },
-  {
-    "plain": "5"
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Pagebreak."
+      },
+      {
+        "ssml": "4"
+      },
+      {
+        "language": "en",
+        "ssml": "And the next pagebreak is in the middle of a sentence."
+      },
+      {
+        "ssml": "Pagebreak."
+      },
+      {
+        "ssml": "5"
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "skip": [
+            "pagebreak"
+          ]
+        },
+        "utterances": [
+          {
+            "language": "en",
+            "ssml": "And the next pagebreak is in the middle of a sentence."
+          }
+        ]
+      },
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "4"
+          },
+          {
+            "language": "en",
+            "ssml": "And the next pagebreak is in the middle of a sentence."
+          },
+          {
+            "ssml": "5"
+          }
+        ]
+      },
+      {
+        "options": {
+          "interruptSentence": true
+        },
+        "utterances": [
+          {
+            "ssml": "Pagebreak."
+          },
+          {
+            "ssml": "4"
+          },
+          {
+            "language": "en",
+            "ssml": "And the next pagebreak is in the middle"
+          },
+          {
+            "ssml": "Pagebreak."
+          },
+          {
+            "ssml": "5"
+          },
+          {
+            "language": "en",
+            "ssml": "of a sentence."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/pagelist-epub-type/gnd.json b/fixtures/pagelist-epub-type/gnd.json
index b16050a..cfed5ea 100644
--- a/fixtures/pagelist-epub-type/gnd.json
+++ b/fixtures/pagelist-epub-type/gnd.json
@@ -1,34 +1,41 @@
 {
   "role": [
-    "navigation",
-    "pagelist"
+    "body"
   ],
   "children": [
     {
       "role": [
-        "list"
+        "navigation",
+        "pagelist"
       ],
       "children": [
         {
           "role": [
-            "listItem"
+            "list"
           ],
-          "text": "Page 1",
-          "textref": "#pg1"
-        },
-        {
-          "role": [
-            "listItem"
-          ],
-          "text": "Page 2",
-          "textref": "#pg2"
-        },
-        {
-          "role": [
-            "listItem"
-          ],
-          "text": "Page 3",
-          "textref": "#pg3"
+          "children": [
+            {
+              "textref": "#pg1",
+              "text": "Page 1",
+              "role": [
+                "listItem"
+              ]
+            },
+            {
+              "textref": "#pg2",
+              "text": "Page 2",
+              "role": [
+                "listItem"
+              ]
+            },
+            {
+              "textref": "#pg3",
+              "text": "Page 3",
+              "role": [
+                "listItem"
+              ]
+            }
+          ]
         }
       ]
     }
diff --git a/fixtures/pagelist-epub-type/input.html b/fixtures/pagelist-epub-type/input.xhtml
similarity index 100%
rename from fixtures/pagelist-epub-type/input.html
rename to fixtures/pagelist-epub-type/input.xhtml
diff --git a/fixtures/pagelist-epub-type/utterances.json b/fixtures/pagelist-epub-type/utterances.json
index 81b6af3..39297e7 100644
--- a/fixtures/pagelist-epub-type/utterances.json
+++ b/fixtures/pagelist-epub-type/utterances.json
@@ -1,11 +1,76 @@
-[
-  {
-    "plain": "Page 1"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the page list."
+      },
+      {
+        "plain": "Page 1"
+      },
+      {
+        "plain": "Page 2"
+      },
+      {
+        "plain": "Page 3"
+      },
+      {
+        "plain": "End of the page list."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "Page 1"
+          },
+          {
+            "plain": "Page 2"
+          },
+          {
+            "plain": "Page 3"
+          }
+        ]
+      }
+    ]
   },
-  {
-    "plain": "Page 2"
-  },
-  {
-    "plain": "Page 3"
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the page list."
+      },
+      {
+        "ssml": "Page 1"
+      },
+      {
+        "ssml": "Page 2"
+      },
+      {
+        "ssml": "Page 3"
+      },
+      {
+        "ssml": "End of the page list."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "Page 1"
+          },
+          {
+            "ssml": "Page 2"
+          },
+          {
+            "ssml": "Page 3"
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/pagelist-role-aria/utterances.json b/fixtures/pagelist-role-aria/utterances.json
index 81b6af3..39297e7 100644
--- a/fixtures/pagelist-role-aria/utterances.json
+++ b/fixtures/pagelist-role-aria/utterances.json
@@ -1,11 +1,76 @@
-[
-  {
-    "plain": "Page 1"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the page list."
+      },
+      {
+        "plain": "Page 1"
+      },
+      {
+        "plain": "Page 2"
+      },
+      {
+        "plain": "Page 3"
+      },
+      {
+        "plain": "End of the page list."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "Page 1"
+          },
+          {
+            "plain": "Page 2"
+          },
+          {
+            "plain": "Page 3"
+          }
+        ]
+      }
+    ]
   },
-  {
-    "plain": "Page 2"
-  },
-  {
-    "plain": "Page 3"
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the page list."
+      },
+      {
+        "ssml": "Page 1"
+      },
+      {
+        "ssml": "Page 2"
+      },
+      {
+        "ssml": "Page 3"
+      },
+      {
+        "ssml": "End of the page list."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "Page 1"
+          },
+          {
+            "ssml": "Page 2"
+          },
+          {
+            "ssml": "Page 3"
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/paragraph-basic/utterances.json b/fixtures/paragraph-basic/utterances.json
index 864bf30..b500747 100644
--- a/fixtures/paragraph-basic/utterances.json
+++ b/fixtures/paragraph-basic/utterances.json
@@ -1,5 +1,16 @@
-[
-  {
-    "plain": "It is a truth universally acknowledged, that a single man in possession of a good fortune, must be in want of a wife."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "It is a truth universally acknowledged, that a single man in possession of a good fortune, must be in want of a wife."
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "It is a truth universally acknowledged, that a single man in possession of a good fortune, must be in want of a wife."
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/paragraph-block-level-language/gnd.json b/fixtures/paragraph-block-level-language/gnd.json
index da5c5df..878352a 100644
--- a/fixtures/paragraph-block-level-language/gnd.json
+++ b/fixtures/paragraph-block-level-language/gnd.json
@@ -1,22 +1,25 @@
 {
+  "role": [
+    "body"
+  ],
   "children": [
     {
+      "text": {
+        "language": "en",
+        "plain": "Hello."
+      },
       "role": [
         "paragraph"
-      ],
-      "text": {
-        "plain": "Hello.",
-        "language": "en"
-      }
+      ]
     },
     {
+      "text": {
+        "language": "fr",
+        "plain": "Bonjour."
+      },
       "role": [
         "paragraph"
-      ],
-      "text": {
-        "plain": "Bonjour.",
-        "language": "fr"
-      }
+      ]
     }
   ]
 }
diff --git a/fixtures/paragraph-block-level-language/utterances.json b/fixtures/paragraph-block-level-language/utterances.json
index a692582..5743f8e 100644
--- a/fixtures/paragraph-block-level-language/utterances.json
+++ b/fixtures/paragraph-block-level-language/utterances.json
@@ -1,10 +1,56 @@
-[
-  {
-    "plain": "Hello.",
-    "language": "en"
+{
+  "plain": {
+    "base": [
+      {
+        "language": "en",
+        "plain": "Hello."
+      },
+      {
+        "language": "fr",
+        "plain": "Bonjour."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "language": "never"
+        },
+        "utterances": [
+          {
+            "plain": "Hello."
+          },
+          {
+            "plain": "Bonjour."
+          }
+        ]
+      }
+    ]
   },
-  {
-    "plain": "Bonjour.",
-    "language": "fr"
+  "ssml": {
+    "base": [
+      {
+        "language": "en",
+        "ssml": "Hello."
+      },
+      {
+        "language": "fr",
+        "ssml": "Bonjour."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "language": "never"
+        },
+        "utterances": [
+          {
+            "ssml": "Hello."
+          },
+          {
+            "ssml": "Bonjour."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/paragraph-document-language/gnd.json b/fixtures/paragraph-document-language/gnd.json
index 1e1cf83..add82dc 100644
--- a/fixtures/paragraph-document-language/gnd.json
+++ b/fixtures/paragraph-document-language/gnd.json
@@ -1,9 +1,16 @@
 {
   "role": [
-    "paragraph"
+    "body"
   ],
-  "text": {
-    "plain": "Bonjour, comment allez-vous ?",
-    "language": "fr"
-  }
+  "children": [
+    {
+      "text": {
+        "language": "fr",
+        "plain": "Bonjour, comment allez-vous ?"
+      },
+      "role": [
+        "paragraph"
+      ]
+    }
+  ]
 }
diff --git a/fixtures/paragraph-document-language/utterances.json b/fixtures/paragraph-document-language/utterances.json
index eaef74d..6daa96e 100644
--- a/fixtures/paragraph-document-language/utterances.json
+++ b/fixtures/paragraph-document-language/utterances.json
@@ -1,6 +1,42 @@
-[
-  {
-    "plain": "Bonjour, comment allez-vous ?",
-    "language": "fr"
+{
+  "plain": {
+    "base": [
+      {
+        "language": "fr",
+        "plain": "Bonjour, comment allez-vous ?"
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "language": "never"
+        },
+        "utterances": [
+          {
+            "plain": "Bonjour, comment allez-vous ?"
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "language": "fr",
+        "ssml": "Bonjour, comment allez-vous ?"
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "language": "never"
+        },
+        "utterances": [
+          {
+            "ssml": "Bonjour, comment allez-vous ?"
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/paragraph-multilingual-lang-attribute/utterances.json b/fixtures/paragraph-multilingual-lang-attribute/utterances.json
index 8377dbf..c0a22aa 100644
--- a/fixtures/paragraph-multilingual-lang-attribute/utterances.json
+++ b/fixtures/paragraph-multilingual-lang-attribute/utterances.json
@@ -1,6 +1,53 @@
-[
-  {
-    "ssml": "Hello <lang xml:lang=\"fr\">bonjour</lang>.",
-    "language": "en"
+{
+  "plain": {
+    "base": [
+      {
+        "language": "en",
+        "plain": "Hello bonjour."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "language": "never"
+        },
+        "utterances": [
+          {
+            "plain": "Hello bonjour."
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "language": "en",
+        "ssml": "Hello <lang xml:lang=\"fr\">bonjour</lang>."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "language": "never"
+        },
+        "utterances": [
+          {
+            "ssml": "Hello bonjour."
+          }
+        ]
+      },
+      {
+        "options": {
+          "language": "block"
+        },
+        "utterances": [
+          {
+            "language": "en",
+            "ssml": "Hello bonjour."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/paragraph-multilingual-nested/utterances.json b/fixtures/paragraph-multilingual-nested/utterances.json
index e280abe..7e1f04e 100644
--- a/fixtures/paragraph-multilingual-nested/utterances.json
+++ b/fixtures/paragraph-multilingual-nested/utterances.json
@@ -1,6 +1,53 @@
-[
-  {
-    "ssml": "Start <lang xml:lang=\"fr\">middle </lang><lang xml:lang=\"es\">nested</lang><lang xml:lang=\"fr\"> end</lang> after.",
-    "language": "en"
+{
+  "plain": {
+    "base": [
+      {
+        "language": "en",
+        "plain": "Start middle nested end after."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "language": "never"
+        },
+        "utterances": [
+          {
+            "plain": "Start middle nested end after."
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "language": "en",
+        "ssml": "Start <lang xml:lang=\"fr\">middle </lang><lang xml:lang=\"es\">nested</lang><lang xml:lang=\"fr\"> end</lang> after."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "language": "never"
+        },
+        "utterances": [
+          {
+            "ssml": "Start middle nested end after."
+          }
+        ]
+      },
+      {
+        "options": {
+          "language": "block"
+        },
+        "utterances": [
+          {
+            "language": "en",
+            "ssml": "Start middle nested end after."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/paragraph-multilingual-repeated-language/utterances.json b/fixtures/paragraph-multilingual-repeated-language/utterances.json
index 9d89c44..91f60c2 100644
--- a/fixtures/paragraph-multilingual-repeated-language/utterances.json
+++ b/fixtures/paragraph-multilingual-repeated-language/utterances.json
@@ -1,6 +1,53 @@
-[
-  {
-    "ssml": "One <lang xml:lang=\"fr\">deux</lang> three <lang xml:lang=\"fr\">quatre</lang> five.",
-    "language": "en"
+{
+  "plain": {
+    "base": [
+      {
+        "language": "en",
+        "plain": "One deux three quatre five."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "language": "never"
+        },
+        "utterances": [
+          {
+            "plain": "One deux three quatre five."
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "language": "en",
+        "ssml": "One <lang xml:lang=\"fr\">deux</lang> three <lang xml:lang=\"fr\">quatre</lang> five."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "language": "never"
+        },
+        "utterances": [
+          {
+            "ssml": "One deux three quatre five."
+          }
+        ]
+      },
+      {
+        "options": {
+          "language": "block"
+        },
+        "utterances": [
+          {
+            "language": "en",
+            "ssml": "One deux three quatre five."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/paragraph-multilingual-ssml-lang/utterances.json b/fixtures/paragraph-multilingual-ssml-lang/utterances.json
index e675f8b..d9d6edc 100644
--- a/fixtures/paragraph-multilingual-ssml-lang/utterances.json
+++ b/fixtures/paragraph-multilingual-ssml-lang/utterances.json
@@ -1,6 +1,53 @@
-[
-  {
-    "ssml": "This job requires a certain <lang xml:lang=\"fr\">savoir faire</lang> that can only be acquired over time.",
-    "language": "en"
+{
+  "plain": {
+    "base": [
+      {
+        "language": "en",
+        "plain": "This job requires a certain savoir faire that can only be acquired over time."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "language": "never"
+        },
+        "utterances": [
+          {
+            "plain": "This job requires a certain savoir faire that can only be acquired over time."
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "language": "en",
+        "ssml": "This job requires a certain <lang xml:lang=\"fr\">savoir faire</lang> that can only be acquired over time."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "language": "never"
+        },
+        "utterances": [
+          {
+            "ssml": "This job requires a certain savoir faire that can only be acquired over time."
+          }
+        ]
+      },
+      {
+        "options": {
+          "language": "block"
+        },
+        "utterances": [
+          {
+            "language": "en",
+            "ssml": "This job requires a certain savoir faire that can only be acquired over time."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/paragraph-multilingual-two-languages/utterances.json b/fixtures/paragraph-multilingual-two-languages/utterances.json
index a3986d0..abcb1ed 100644
--- a/fixtures/paragraph-multilingual-two-languages/utterances.json
+++ b/fixtures/paragraph-multilingual-two-languages/utterances.json
@@ -1,6 +1,53 @@
-[
-  {
-    "ssml": "Hello <lang xml:lang=\"fr\">bonjour</lang> and <lang xml:lang=\"es\">hola</lang> there.",
-    "language": "en"
+{
+  "plain": {
+    "base": [
+      {
+        "language": "en",
+        "plain": "Hello bonjour and hola there."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "language": "never"
+        },
+        "utterances": [
+          {
+            "plain": "Hello bonjour and hola there."
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "language": "en",
+        "ssml": "Hello <lang xml:lang=\"fr\">bonjour</lang> and <lang xml:lang=\"es\">hola</lang> there."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "language": "never"
+        },
+        "utterances": [
+          {
+            "ssml": "Hello bonjour and hola there."
+          }
+        ]
+      },
+      {
+        "options": {
+          "language": "block"
+        },
+        "utterances": [
+          {
+            "language": "en",
+            "ssml": "Hello bonjour and hola there."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/part-epub-type/gnd.json b/fixtures/part-epub-type/gnd.json
index d7f29f2..d37f94a 100644
--- a/fixtures/part-epub-type/gnd.json
+++ b/fixtures/part-epub-type/gnd.json
@@ -1,14 +1,21 @@
 {
   "role": [
-    "section",
-    "part"
+    "body"
   ],
   "children": [
     {
       "role": [
-        "heading1"
+        "section",
+        "part"
       ],
-      "text": "Title of the part"
+      "children": [
+        {
+          "text": "Title of the part",
+          "role": [
+            "heading1"
+          ]
+        }
+      ]
     }
   ]
 }
diff --git a/fixtures/part-epub-type/input.html b/fixtures/part-epub-type/input.xhtml
similarity index 100%
rename from fixtures/part-epub-type/input.html
rename to fixtures/part-epub-type/input.xhtml
diff --git a/fixtures/part-epub-type/utterances.json b/fixtures/part-epub-type/utterances.json
index 61814f5..d655e40 100644
--- a/fixtures/part-epub-type/utterances.json
+++ b/fixtures/part-epub-type/utterances.json
@@ -1,5 +1,58 @@
-[
-  {
-    "plain": "Title of the part"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the part."
+      },
+      {
+        "plain": "Heading level 1."
+      },
+      {
+        "plain": "Title of the part"
+      },
+      {
+        "plain": "End of the part."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "Title of the part"
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the part."
+      },
+      {
+        "ssml": "Heading level 1."
+      },
+      {
+        "ssml": "Title of the part"
+      },
+      {
+        "ssml": "End of the part."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "Title of the part"
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/part-role-aria/utterances.json b/fixtures/part-role-aria/utterances.json
index 61814f5..d655e40 100644
--- a/fixtures/part-role-aria/utterances.json
+++ b/fixtures/part-role-aria/utterances.json
@@ -1,5 +1,58 @@
-[
-  {
-    "plain": "Title of the part"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the part."
+      },
+      {
+        "plain": "Heading level 1."
+      },
+      {
+        "plain": "Title of the part"
+      },
+      {
+        "plain": "End of the part."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "Title of the part"
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the part."
+      },
+      {
+        "ssml": "Heading level 1."
+      },
+      {
+        "ssml": "Title of the part"
+      },
+      {
+        "ssml": "End of the part."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "Title of the part"
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/preface-epub-type/gnd.json b/fixtures/preface-epub-type/gnd.json
index 20e7432..609a3f4 100644
--- a/fixtures/preface-epub-type/gnd.json
+++ b/fixtures/preface-epub-type/gnd.json
@@ -1,6 +1,13 @@
 {
   "role": [
-    "preface"
+    "body"
   ],
-  "text": "This edition adds a chapter on automation."
+  "children": [
+    {
+      "text": "This edition adds a chapter on automation.",
+      "role": [
+        "preface"
+      ]
+    }
+  ]
 }
diff --git a/fixtures/preface-epub-type/input.html b/fixtures/preface-epub-type/input.xhtml
similarity index 100%
rename from fixtures/preface-epub-type/input.html
rename to fixtures/preface-epub-type/input.xhtml
diff --git a/fixtures/preface-epub-type/utterances.json b/fixtures/preface-epub-type/utterances.json
index d6aa5e8..e9424ef 100644
--- a/fixtures/preface-epub-type/utterances.json
+++ b/fixtures/preface-epub-type/utterances.json
@@ -1,5 +1,52 @@
-[
-  {
-    "plain": "This edition adds a chapter on automation."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the preface."
+      },
+      {
+        "plain": "This edition adds a chapter on automation."
+      },
+      {
+        "plain": "End of the preface."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "This edition adds a chapter on automation."
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the preface."
+      },
+      {
+        "ssml": "This edition adds a chapter on automation."
+      },
+      {
+        "ssml": "End of the preface."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "This edition adds a chapter on automation."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/preface-role-aria/utterances.json b/fixtures/preface-role-aria/utterances.json
index d6aa5e8..e9424ef 100644
--- a/fixtures/preface-role-aria/utterances.json
+++ b/fixtures/preface-role-aria/utterances.json
@@ -1,5 +1,52 @@
-[
-  {
-    "plain": "This edition adds a chapter on automation."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the preface."
+      },
+      {
+        "plain": "This edition adds a chapter on automation."
+      },
+      {
+        "plain": "End of the preface."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "This edition adds a chapter on automation."
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the preface."
+      },
+      {
+        "ssml": "This edition adds a chapter on automation."
+      },
+      {
+        "ssml": "End of the preface."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "This edition adds a chapter on automation."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/preformatted-html-native/utterances.json b/fixtures/preformatted-html-native/utterances.json
index 4165e9f..27ba9d5 100644
--- a/fixtures/preformatted-html-native/utterances.json
+++ b/fixtures/preformatted-html-native/utterances.json
@@ -1,5 +1,16 @@
-[
-  {
-    "plain": "10 PRINT \"HELLO\" 20 GOTO 10"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "10 PRINT \"HELLO\" 20 GOTO 10"
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "10 PRINT \"HELLO\" 20 GOTO 10"
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/presentation-role-aria/utterances.json b/fixtures/presentation-role-aria/utterances.json
index a80ff25..604d9ca 100644
--- a/fixtures/presentation-role-aria/utterances.json
+++ b/fixtures/presentation-role-aria/utterances.json
@@ -1,5 +1,16 @@
-[
-  {
-    "plain": "Decorative content with no semantic meaning."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Decorative content with no semantic meaning."
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Decorative content with no semantic meaning."
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/prologue-epub-type/gnd.json b/fixtures/prologue-epub-type/gnd.json
index 46d6f5b..5d1409f 100644
--- a/fixtures/prologue-epub-type/gnd.json
+++ b/fixtures/prologue-epub-type/gnd.json
@@ -1,6 +1,13 @@
 {
   "role": [
-    "prologue"
+    "body"
   ],
-  "text": "Before the lamp was ever lit, the rock was already feared."
+  "children": [
+    {
+      "text": "Before the lamp was ever lit, the rock was already feared.",
+      "role": [
+        "prologue"
+      ]
+    }
+  ]
 }
diff --git a/fixtures/prologue-epub-type/input.html b/fixtures/prologue-epub-type/input.xhtml
similarity index 100%
rename from fixtures/prologue-epub-type/input.html
rename to fixtures/prologue-epub-type/input.xhtml
diff --git a/fixtures/prologue-epub-type/utterances.json b/fixtures/prologue-epub-type/utterances.json
index 024b3e7..5aacdaf 100644
--- a/fixtures/prologue-epub-type/utterances.json
+++ b/fixtures/prologue-epub-type/utterances.json
@@ -1,5 +1,52 @@
-[
-  {
-    "plain": "Before the lamp was ever lit, the rock was already feared."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the prologue."
+      },
+      {
+        "plain": "Before the lamp was ever lit, the rock was already feared."
+      },
+      {
+        "plain": "End of the prologue."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "Before the lamp was ever lit, the rock was already feared."
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the prologue."
+      },
+      {
+        "ssml": "Before the lamp was ever lit, the rock was already feared."
+      },
+      {
+        "ssml": "End of the prologue."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "Before the lamp was ever lit, the rock was already feared."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/prologue-role-aria/utterances.json b/fixtures/prologue-role-aria/utterances.json
index 024b3e7..5aacdaf 100644
--- a/fixtures/prologue-role-aria/utterances.json
+++ b/fixtures/prologue-role-aria/utterances.json
@@ -1,5 +1,52 @@
-[
-  {
-    "plain": "Before the lamp was ever lit, the rock was already feared."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the prologue."
+      },
+      {
+        "plain": "Before the lamp was ever lit, the rock was already feared."
+      },
+      {
+        "plain": "End of the prologue."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "Before the lamp was ever lit, the rock was already feared."
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the prologue."
+      },
+      {
+        "ssml": "Before the lamp was ever lit, the rock was already feared."
+      },
+      {
+        "ssml": "End of the prologue."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "Before the lamp was ever lit, the rock was already feared."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/pullquote-epub-type/gnd.json b/fixtures/pullquote-epub-type/gnd.json
index e6171ba..e374f2c 100644
--- a/fixtures/pullquote-epub-type/gnd.json
+++ b/fixtures/pullquote-epub-type/gnd.json
@@ -1,7 +1,14 @@
 {
   "role": [
-    "aside",
-    "pullquote"
+    "body"
   ],
-  "text": "The lamp still turns, though no one climbs the stairs anymore."
+  "children": [
+    {
+      "text": "The lamp still turns, though no one climbs the stairs anymore.",
+      "role": [
+        "aside",
+        "pullquote"
+      ]
+    }
+  ]
 }
diff --git a/fixtures/pullquote-epub-type/input.html b/fixtures/pullquote-epub-type/input.xhtml
similarity index 100%
rename from fixtures/pullquote-epub-type/input.html
rename to fixtures/pullquote-epub-type/input.xhtml
diff --git a/fixtures/pullquote-epub-type/utterances.json b/fixtures/pullquote-epub-type/utterances.json
index d2d00eb..cd626f8 100644
--- a/fixtures/pullquote-epub-type/utterances.json
+++ b/fixtures/pullquote-epub-type/utterances.json
@@ -1,5 +1,90 @@
-[
-  {
-    "plain": "The lamp still turns, though no one climbs the stairs anymore."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the aside."
+      },
+      {
+        "plain": "Pull quote."
+      },
+      {
+        "plain": "The lamp still turns, though no one climbs the stairs anymore."
+      },
+      {
+        "plain": "End of the aside."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "skip": [
+            "aside"
+          ]
+        },
+        "utterances": []
+      },
+      {
+        "options": {
+          "skip": [
+            "pullquote"
+          ]
+        },
+        "utterances": []
+      },
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "The lamp still turns, though no one climbs the stairs anymore."
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the aside."
+      },
+      {
+        "ssml": "Pull quote."
+      },
+      {
+        "ssml": "The lamp still turns, though no one climbs the stairs anymore."
+      },
+      {
+        "ssml": "End of the aside."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "skip": [
+            "aside"
+          ]
+        },
+        "utterances": []
+      },
+      {
+        "options": {
+          "skip": [
+            "pullquote"
+          ]
+        },
+        "utterances": []
+      },
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "The lamp still turns, though no one climbs the stairs anymore."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/pullquote-role-aria/utterances.json b/fixtures/pullquote-role-aria/utterances.json
index d2d00eb..70184ff 100644
--- a/fixtures/pullquote-role-aria/utterances.json
+++ b/fixtures/pullquote-role-aria/utterances.json
@@ -1,5 +1,62 @@
-[
-  {
-    "plain": "The lamp still turns, though no one climbs the stairs anymore."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Pull quote."
+      },
+      {
+        "plain": "The lamp still turns, though no one climbs the stairs anymore."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "skip": [
+            "pullquote"
+          ]
+        },
+        "utterances": []
+      },
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "The lamp still turns, though no one climbs the stairs anymore."
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Pull quote."
+      },
+      {
+        "ssml": "The lamp still turns, though no one climbs the stairs anymore."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "skip": [
+            "pullquote"
+          ]
+        },
+        "utterances": []
+      },
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "The lamp still turns, though no one climbs the stairs anymore."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/qna-epub-type/gnd.json b/fixtures/qna-epub-type/gnd.json
index 6d27744..a1bac48 100644
--- a/fixtures/qna-epub-type/gnd.json
+++ b/fixtures/qna-epub-type/gnd.json
@@ -1,7 +1,14 @@
 {
   "role": [
-    "section",
-    "qna"
+    "body"
   ],
-  "text": "Q: How often was the lamp refueled? A: Nightly, by hand."
+  "children": [
+    {
+      "text": "Q: How often was the lamp refueled? A: Nightly, by hand.",
+      "role": [
+        "section",
+        "qna"
+      ]
+    }
+  ]
 }
diff --git a/fixtures/qna-epub-type/input.html b/fixtures/qna-epub-type/input.xhtml
similarity index 100%
rename from fixtures/qna-epub-type/input.html
rename to fixtures/qna-epub-type/input.xhtml
diff --git a/fixtures/qna-epub-type/utterances.json b/fixtures/qna-epub-type/utterances.json
index 254ec25..acd2852 100644
--- a/fixtures/qna-epub-type/utterances.json
+++ b/fixtures/qna-epub-type/utterances.json
@@ -1,5 +1,52 @@
-[
-  {
-    "plain": "Q: How often was the lamp refueled? A: Nightly, by hand."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the questions and answers."
+      },
+      {
+        "plain": "Q: How often was the lamp refueled? A: Nightly, by hand."
+      },
+      {
+        "plain": "End of the questions and answers."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "Q: How often was the lamp refueled? A: Nightly, by hand."
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the questions and answers."
+      },
+      {
+        "ssml": "Q: How often was the lamp refueled? A: Nightly, by hand."
+      },
+      {
+        "ssml": "End of the questions and answers."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "Q: How often was the lamp refueled? A: Nightly, by hand."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/qna-role-aria/utterances.json b/fixtures/qna-role-aria/utterances.json
index 254ec25..acd2852 100644
--- a/fixtures/qna-role-aria/utterances.json
+++ b/fixtures/qna-role-aria/utterances.json
@@ -1,5 +1,52 @@
-[
-  {
-    "plain": "Q: How often was the lamp refueled? A: Nightly, by hand."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the questions and answers."
+      },
+      {
+        "plain": "Q: How often was the lamp refueled? A: Nightly, by hand."
+      },
+      {
+        "plain": "End of the questions and answers."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "Q: How often was the lamp refueled? A: Nightly, by hand."
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the questions and answers."
+      },
+      {
+        "ssml": "Q: How often was the lamp refueled? A: Nightly, by hand."
+      },
+      {
+        "ssml": "End of the questions and answers."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "Q: How often was the lamp refueled? A: Nightly, by hand."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/region-role-aria/utterances.json b/fixtures/region-role-aria/utterances.json
index a3e3271..f241373 100644
--- a/fixtures/region-role-aria/utterances.json
+++ b/fixtures/region-role-aria/utterances.json
@@ -1,5 +1,16 @@
-[
-  {
-    "plain": "A named region of interest within the page."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "A named region of interest within the page."
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "A named region of interest within the page."
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/section-html-native/utterances.json b/fixtures/section-html-native/utterances.json
index eb94260..fad21cd 100644
--- a/fixtures/section-html-native/utterances.json
+++ b/fixtures/section-html-native/utterances.json
@@ -1,5 +1,16 @@
-[
-  {
-    "plain": "The lighthouse was decommissioned in 1998, though its light still functions as a private aid to navigation."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "The lighthouse was decommissioned in 1998, though its light still functions as a private aid to navigation."
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "The lighthouse was decommissioned in 1998, though its light still functions as a private aid to navigation."
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/separator-html-native/utterances.json b/fixtures/separator-html-native/utterances.json
index da51e76..5049830 100644
--- a/fixtures/separator-html-native/utterances.json
+++ b/fixtures/separator-html-native/utterances.json
@@ -1,8 +1,22 @@
-[
-  {
-    "plain": "Section one."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Section one."
+      },
+      {
+        "plain": "Section two."
+      }
+    ]
   },
-  {
-    "plain": "Section two."
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Section one."
+      },
+      {
+        "ssml": "Section two."
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/separator-role-aria/utterances.json b/fixtures/separator-role-aria/utterances.json
index da51e76..5049830 100644
--- a/fixtures/separator-role-aria/utterances.json
+++ b/fixtures/separator-role-aria/utterances.json
@@ -1,8 +1,22 @@
-[
-  {
-    "plain": "Section one."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Section one."
+      },
+      {
+        "plain": "Section two."
+      }
+    ]
   },
-  {
-    "plain": "Section two."
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Section one."
+      },
+      {
+        "ssml": "Section two."
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/subtitle-epub-type/gnd.json b/fixtures/subtitle-epub-type/gnd.json
index 8e35c8f..b957f97 100644
--- a/fixtures/subtitle-epub-type/gnd.json
+++ b/fixtures/subtitle-epub-type/gnd.json
@@ -1,6 +1,13 @@
 {
   "role": [
-    "subtitle"
+    "body"
   ],
-  "text": "A History of Coastal Lights"
+  "children": [
+    {
+      "text": "A History of Coastal Lights",
+      "role": [
+        "subtitle"
+      ]
+    }
+  ]
 }
diff --git a/fixtures/subtitle-epub-type/input.html b/fixtures/subtitle-epub-type/input.xhtml
similarity index 100%
rename from fixtures/subtitle-epub-type/input.html
rename to fixtures/subtitle-epub-type/input.xhtml
diff --git a/fixtures/subtitle-epub-type/utterances.json b/fixtures/subtitle-epub-type/utterances.json
index b162db7..2cb34e9 100644
--- a/fixtures/subtitle-epub-type/utterances.json
+++ b/fixtures/subtitle-epub-type/utterances.json
@@ -1,5 +1,46 @@
-[
-  {
-    "plain": "A History of Coastal Lights"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Subtitle."
+      },
+      {
+        "plain": "A History of Coastal Lights"
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "A History of Coastal Lights"
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Subtitle."
+      },
+      {
+        "ssml": "A History of Coastal Lights"
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "A History of Coastal Lights"
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/subtitle-role-aria/utterances.json b/fixtures/subtitle-role-aria/utterances.json
index b162db7..2cb34e9 100644
--- a/fixtures/subtitle-role-aria/utterances.json
+++ b/fixtures/subtitle-role-aria/utterances.json
@@ -1,5 +1,46 @@
-[
-  {
-    "plain": "A History of Coastal Lights"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Subtitle."
+      },
+      {
+        "plain": "A History of Coastal Lights"
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "A History of Coastal Lights"
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Subtitle."
+      },
+      {
+        "ssml": "A History of Coastal Lights"
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "A History of Coastal Lights"
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/summary-html-native/utterances.json b/fixtures/summary-html-native/utterances.json
index 61a9134..85e7604 100644
--- a/fixtures/summary-html-native/utterances.json
+++ b/fixtures/summary-html-native/utterances.json
@@ -1,5 +1,16 @@
-[
-  {
-    "plain": "Click to expand"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Click to expand"
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Click to expand"
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/table-html-native/utterances.json b/fixtures/table-html-native/utterances.json
index 1e8b76c..3d48269 100644
--- a/fixtures/table-html-native/utterances.json
+++ b/fixtures/table-html-native/utterances.json
@@ -1,20 +1,112 @@
-[
-  {
-    "plain": "Name"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the table."
+      },
+      {
+        "plain": "Name"
+      },
+      {
+        "plain": "Role"
+      },
+      {
+        "plain": "Ada"
+      },
+      {
+        "plain": "Engineer"
+      },
+      {
+        "plain": "Grace"
+      },
+      {
+        "plain": "Admiral"
+      },
+      {
+        "plain": "End of the table."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "Name"
+          },
+          {
+            "plain": "Role"
+          },
+          {
+            "plain": "Ada"
+          },
+          {
+            "plain": "Engineer"
+          },
+          {
+            "plain": "Grace"
+          },
+          {
+            "plain": "Admiral"
+          }
+        ]
+      }
+    ]
   },
-  {
-    "plain": "Role"
-  },
-  {
-    "plain": "Ada"
-  },
-  {
-    "plain": "Engineer"
-  },
-  {
-    "plain": "Grace"
-  },
-  {
-    "plain": "Admiral"
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the table."
+      },
+      {
+        "ssml": "Name"
+      },
+      {
+        "ssml": "Role"
+      },
+      {
+        "ssml": "Ada"
+      },
+      {
+        "ssml": "Engineer"
+      },
+      {
+        "ssml": "Grace"
+      },
+      {
+        "ssml": "Admiral"
+      },
+      {
+        "ssml": "End of the table."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "Name"
+          },
+          {
+            "ssml": "Role"
+          },
+          {
+            "ssml": "Ada"
+          },
+          {
+            "ssml": "Engineer"
+          },
+          {
+            "ssml": "Grace"
+          },
+          {
+            "ssml": "Admiral"
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/table-role-aria/utterances.json b/fixtures/table-role-aria/utterances.json
index 1e8b76c..3d48269 100644
--- a/fixtures/table-role-aria/utterances.json
+++ b/fixtures/table-role-aria/utterances.json
@@ -1,20 +1,112 @@
-[
-  {
-    "plain": "Name"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the table."
+      },
+      {
+        "plain": "Name"
+      },
+      {
+        "plain": "Role"
+      },
+      {
+        "plain": "Ada"
+      },
+      {
+        "plain": "Engineer"
+      },
+      {
+        "plain": "Grace"
+      },
+      {
+        "plain": "Admiral"
+      },
+      {
+        "plain": "End of the table."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "Name"
+          },
+          {
+            "plain": "Role"
+          },
+          {
+            "plain": "Ada"
+          },
+          {
+            "plain": "Engineer"
+          },
+          {
+            "plain": "Grace"
+          },
+          {
+            "plain": "Admiral"
+          }
+        ]
+      }
+    ]
   },
-  {
-    "plain": "Role"
-  },
-  {
-    "plain": "Ada"
-  },
-  {
-    "plain": "Engineer"
-  },
-  {
-    "plain": "Grace"
-  },
-  {
-    "plain": "Admiral"
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the table."
+      },
+      {
+        "ssml": "Name"
+      },
+      {
+        "ssml": "Role"
+      },
+      {
+        "ssml": "Ada"
+      },
+      {
+        "ssml": "Engineer"
+      },
+      {
+        "ssml": "Grace"
+      },
+      {
+        "ssml": "Admiral"
+      },
+      {
+        "ssml": "End of the table."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "Name"
+          },
+          {
+            "ssml": "Role"
+          },
+          {
+            "ssml": "Ada"
+          },
+          {
+            "ssml": "Engineer"
+          },
+          {
+            "ssml": "Grace"
+          },
+          {
+            "ssml": "Admiral"
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/term-epub-type/gnd.json b/fixtures/term-epub-type/gnd.json
index 3eaba6c..71c4588 100644
--- a/fixtures/term-epub-type/gnd.json
+++ b/fixtures/term-epub-type/gnd.json
@@ -1,13 +1,20 @@
 {
   "role": [
-    "glossary"
+    "body"
   ],
   "children": [
     {
       "role": [
-        "term"
+        "glossary"
       ],
-      "text": "lighthouse"
+      "children": [
+        {
+          "text": "lighthouse",
+          "role": [
+            "term"
+          ]
+        }
+      ]
     }
   ]
 }
diff --git a/fixtures/term-epub-type/input.html b/fixtures/term-epub-type/input.xhtml
similarity index 100%
rename from fixtures/term-epub-type/input.html
rename to fixtures/term-epub-type/input.xhtml
diff --git a/fixtures/term-epub-type/utterances.json b/fixtures/term-epub-type/utterances.json
index 5194285..7565984 100644
--- a/fixtures/term-epub-type/utterances.json
+++ b/fixtures/term-epub-type/utterances.json
@@ -1,5 +1,52 @@
-[
-  {
-    "plain": "lighthouse"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the glossary."
+      },
+      {
+        "plain": "lighthouse"
+      },
+      {
+        "plain": "End of the glossary."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "lighthouse"
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the glossary."
+      },
+      {
+        "ssml": "lighthouse"
+      },
+      {
+        "ssml": "End of the glossary."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "lighthouse"
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/term-html-native/utterances.json b/fixtures/term-html-native/utterances.json
index 5194285..ad275b8 100644
--- a/fixtures/term-html-native/utterances.json
+++ b/fixtures/term-html-native/utterances.json
@@ -1,5 +1,16 @@
-[
-  {
-    "plain": "lighthouse"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "lighthouse"
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "lighthouse"
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/term-role-aria/utterances.json b/fixtures/term-role-aria/utterances.json
index 5194285..ad275b8 100644
--- a/fixtures/term-role-aria/utterances.json
+++ b/fixtures/term-role-aria/utterances.json
@@ -1,5 +1,16 @@
-[
-  {
-    "plain": "lighthouse"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "lighthouse"
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "lighthouse"
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/tip-epub-type/gnd.json b/fixtures/tip-epub-type/gnd.json
index 0d5d353..4b71d32 100644
--- a/fixtures/tip-epub-type/gnd.json
+++ b/fixtures/tip-epub-type/gnd.json
@@ -1,7 +1,14 @@
 {
   "role": [
-    "aside",
-    "tip"
+    "body"
   ],
-  "text": "Tip: wind the mechanism fully before dusk."
+  "children": [
+    {
+      "text": "Tip: wind the mechanism fully before dusk.",
+      "role": [
+        "aside",
+        "tip"
+      ]
+    }
+  ]
 }
diff --git a/fixtures/tip-epub-type/input.html b/fixtures/tip-epub-type/input.xhtml
similarity index 100%
rename from fixtures/tip-epub-type/input.html
rename to fixtures/tip-epub-type/input.xhtml
diff --git a/fixtures/tip-epub-type/utterances.json b/fixtures/tip-epub-type/utterances.json
index 50ed99a..df40608 100644
--- a/fixtures/tip-epub-type/utterances.json
+++ b/fixtures/tip-epub-type/utterances.json
@@ -1,5 +1,74 @@
-[
-  {
-    "plain": "Tip: wind the mechanism fully before dusk."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the aside."
+      },
+      {
+        "plain": "Tip."
+      },
+      {
+        "plain": "Tip: wind the mechanism fully before dusk."
+      },
+      {
+        "plain": "End of the aside."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "skip": [
+            "aside"
+          ]
+        },
+        "utterances": []
+      },
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "Tip: wind the mechanism fully before dusk."
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the aside."
+      },
+      {
+        "ssml": "Tip."
+      },
+      {
+        "ssml": "Tip: wind the mechanism fully before dusk."
+      },
+      {
+        "ssml": "End of the aside."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "skip": [
+            "aside"
+          ]
+        },
+        "utterances": []
+      },
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "Tip: wind the mechanism fully before dusk."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/tip-role-aria/utterances.json b/fixtures/tip-role-aria/utterances.json
index 50ed99a..1f40d13 100644
--- a/fixtures/tip-role-aria/utterances.json
+++ b/fixtures/tip-role-aria/utterances.json
@@ -1,5 +1,46 @@
-[
-  {
-    "plain": "Tip: wind the mechanism fully before dusk."
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Tip."
+      },
+      {
+        "plain": "Tip: wind the mechanism fully before dusk."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "Tip: wind the mechanism fully before dusk."
+          }
+        ]
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Tip."
+      },
+      {
+        "ssml": "Tip: wind the mechanism fully before dusk."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "Tip: wind the mechanism fully before dusk."
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/toc-epub-type/gnd.json b/fixtures/toc-epub-type/gnd.json
index 099dbf9..0a8b9ff 100644
--- a/fixtures/toc-epub-type/gnd.json
+++ b/fixtures/toc-epub-type/gnd.json
@@ -1,34 +1,41 @@
 {
   "role": [
-    "navigation",
-    "toc"
+    "body"
   ],
   "children": [
     {
       "role": [
-        "list"
+        "navigation",
+        "toc"
       ],
       "children": [
         {
           "role": [
-            "listItem"
+            "list"
           ],
-          "text": "Chapter One",
-          "textref": "chapter1.xhtml"
-        },
-        {
-          "role": [
-            "listItem"
-          ],
-          "text": "Chapter Two",
-          "textref": "chapter2.xhtml"
-        },
-        {
-          "role": [
-            "listItem"
-          ],
-          "text": "Chapter Three",
-          "textref": "chapter3.xhtml"
+          "children": [
+            {
+              "textref": "chapter1.xhtml",
+              "text": "Chapter One",
+              "role": [
+                "listItem"
+              ]
+            },
+            {
+              "textref": "chapter2.xhtml",
+              "text": "Chapter Two",
+              "role": [
+                "listItem"
+              ]
+            },
+            {
+              "textref": "chapter3.xhtml",
+              "text": "Chapter Three",
+              "role": [
+                "listItem"
+              ]
+            }
+          ]
         }
       ]
     }
diff --git a/fixtures/toc-epub-type/input.html b/fixtures/toc-epub-type/input.xhtml
similarity index 100%
rename from fixtures/toc-epub-type/input.html
rename to fixtures/toc-epub-type/input.xhtml
diff --git a/fixtures/toc-epub-type/utterances.json b/fixtures/toc-epub-type/utterances.json
index 3f1861e..70aef17 100644
--- a/fixtures/toc-epub-type/utterances.json
+++ b/fixtures/toc-epub-type/utterances.json
@@ -1,11 +1,92 @@
-[
-  {
-    "plain": "Chapter One"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the table of contents."
+      },
+      {
+        "plain": "Chapter One"
+      },
+      {
+        "plain": "Chapter Two"
+      },
+      {
+        "plain": "Chapter Three"
+      },
+      {
+        "plain": "End of the table of contents."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "skip": [
+            "toc"
+          ]
+        },
+        "utterances": []
+      },
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "Chapter One"
+          },
+          {
+            "plain": "Chapter Two"
+          },
+          {
+            "plain": "Chapter Three"
+          }
+        ]
+      }
+    ]
   },
-  {
-    "plain": "Chapter Two"
-  },
-  {
-    "plain": "Chapter Three"
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the table of contents."
+      },
+      {
+        "ssml": "Chapter One"
+      },
+      {
+        "ssml": "Chapter Two"
+      },
+      {
+        "ssml": "Chapter Three"
+      },
+      {
+        "ssml": "End of the table of contents."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "skip": [
+            "toc"
+          ]
+        },
+        "utterances": []
+      },
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "Chapter One"
+          },
+          {
+            "ssml": "Chapter Two"
+          },
+          {
+            "ssml": "Chapter Three"
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/toc-role-aria/utterances.json b/fixtures/toc-role-aria/utterances.json
index 3f1861e..70aef17 100644
--- a/fixtures/toc-role-aria/utterances.json
+++ b/fixtures/toc-role-aria/utterances.json
@@ -1,11 +1,92 @@
-[
-  {
-    "plain": "Chapter One"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "Start of the table of contents."
+      },
+      {
+        "plain": "Chapter One"
+      },
+      {
+        "plain": "Chapter Two"
+      },
+      {
+        "plain": "Chapter Three"
+      },
+      {
+        "plain": "End of the table of contents."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "skip": [
+            "toc"
+          ]
+        },
+        "utterances": []
+      },
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "plain": "Chapter One"
+          },
+          {
+            "plain": "Chapter Two"
+          },
+          {
+            "plain": "Chapter Three"
+          }
+        ]
+      }
+    ]
   },
-  {
-    "plain": "Chapter Two"
-  },
-  {
-    "plain": "Chapter Three"
+  "ssml": {
+    "base": [
+      {
+        "ssml": "Start of the table of contents."
+      },
+      {
+        "ssml": "Chapter One"
+      },
+      {
+        "ssml": "Chapter Two"
+      },
+      {
+        "ssml": "Chapter Three"
+      },
+      {
+        "ssml": "End of the table of contents."
+      }
+    ],
+    "variants": [
+      {
+        "options": {
+          "skip": [
+            "toc"
+          ]
+        },
+        "utterances": []
+      },
+      {
+        "options": {
+          "contextualize": false
+        },
+        "utterances": [
+          {
+            "ssml": "Chapter One"
+          },
+          {
+            "ssml": "Chapter Two"
+          },
+          {
+            "ssml": "Chapter Three"
+          }
+        ]
+      }
+    ]
   }
-]
+}
diff --git a/fixtures/video-html-native/utterances.json b/fixtures/video-html-native/utterances.json
index 352df36..44003f3 100644
--- a/fixtures/video-html-native/utterances.json
+++ b/fixtures/video-html-native/utterances.json
@@ -1,5 +1,16 @@
-[
-  {
-    "plain": "The lamp mechanism rotating at dusk"
+{
+  "plain": {
+    "base": [
+      {
+        "plain": "The lamp mechanism rotating at dusk"
+      }
+    ]
+  },
+  "ssml": {
+    "base": [
+      {
+        "ssml": "The lamp mechanism rotating at dusk"
+      }
+    ]
   }
-]
+}
diff --git a/package.json b/package.json
index 84e7b6f..a0b10bf 100644
--- a/package.json
+++ b/package.json
@@ -42,6 +42,7 @@
     "test:utterances": "NODE_NO_WARNINGS=1 ava test/utterances/*.test.ts",
     "generate-metadata": "node scripts/generate-metadata.js",
     "generate-fixtures-manifest": "node scripts/build-fixtures-manifest.js",
+    "generate-utterances": "npm run build && node scripts/generate-utterances.js",
     "clean": "rimraf ./build",
     "build": "vite build",
     "start": "http-server ./",
diff --git a/scripts/build-fixtures-manifest.js b/scripts/build-fixtures-manifest.js
index 65b122f..a2e461a 100644
--- a/scripts/build-fixtures-manifest.js
+++ b/scripts/build-fixtures-manifest.js
@@ -24,7 +24,8 @@ const manifest = fixtureIds.map((id) => {
   const dir = path.join(FIXTURES_DIR, id);
   const meta = JSON.parse(fs.readFileSync(path.join(dir, "meta.json"), "utf-8"));
 
-  for (const file of ["input.html", "gnd.json", "utterances.json"]) {
+  const inputFile = fs.existsSync(path.join(dir, "input.xhtml")) ? "input.xhtml" : "input.html";
+  for (const file of [inputFile, "gnd.json", "utterances.json"]) {
     if (!fs.existsSync(path.join(dir, file))) {
       throw new Error(`fixtures/${id} is missing ${file}`);
     }
@@ -32,26 +33,18 @@ const manifest = fixtureIds.map((id) => {
   if (meta.id !== id) {
     throw new Error(`fixtures/${id}/meta.json has id "${meta.id}", expected "${id}"`);
   }
-  if (meta.skip && !fs.existsSync(path.join(dir, "utterances-skipped.json"))) {
-    throw new Error(`fixtures/${id} sets meta.skip but is missing utterances-skipped.json`);
-  }
 
-  const entry = {
+  return {
     id,
     dir: id,
     role: meta.role,
     description: meta.description,
     files: {
-      input: "input.html",
+      input: inputFile,
       gnd: "gnd.json",
       utterances: "utterances.json",
     },
   };
-  if (meta.skip) {
-    entry.skip = meta.skip;
-    entry.files.utterancesSkipped = "utterances-skipped.json";
-  }
-  return entry;
 });
 
 const ids = manifest.map((e) => e.id);
diff --git a/scripts/generate-utterances.js b/scripts/generate-utterances.js
new file mode 100644
index 0000000..eef52ec
--- /dev/null
+++ b/scripts/generate-utterances.js
@@ -0,0 +1,99 @@
+import { readFileSync, writeFileSync, readdirSync } from "fs";
+import path from "path";
+import { fileURLToPath } from "url";
+
+const __dirname = path.dirname(fileURLToPath(import.meta.url));
+const FIXTURES_DIR = path.join(__dirname, "../fixtures");
+
+// Regenerates every fixture's utterances.json (both `plain`/`ssml` branches'
+// `base` and option `variants`) from its gnd.json, using the actual
+// @readium/speech build — the exact same extractUtterances() a consumer
+// would call. Run this after any change to extractUtterances.ts,
+// announcements.ts, or roles.ts's skippableRoles that should propagate to
+// the fixture suite (e.g. rewording an announcement, adding a role's
+// contextualization). `npm run build` first.
+//
+// This is *not* a substitute for reviewing what changed: utterances.json is
+// still the ground truth other (non-TypeScript) implementations are meant
+// to match, so a diff this script produces should be read over — did the
+// change do what was intended, everywhere it applies — not blindly
+// committed.
+let mod;
+try {
+  mod = await import("../build/index.js");
+} catch (err) {
+  console.error("Run `npm run build` first — could not import build/index.js.");
+  throw err;
+}
+const { extractUtterances, skippableRoles } = mod;
+
+function expectedTopLevel(gnd) {
+  if (gnd && typeof gnd === "object" && !Array.isArray(gnd)) {
+    const keys = Object.keys(gnd);
+    if (keys.length === 1 && keys[0] === "children") return gnd.children;
+  }
+  return [gnd];
+}
+
+function collectRoles(nodes, acc = new Set()) {
+  for (const node of nodes) {
+    for (const role of node.role ?? []) acc.add(role);
+    if (node.children) collectRoles(node.children, acc);
+  }
+  return acc;
+}
+
+function containsPlaceholder(gnd) {
+  return JSON.stringify(gnd).includes("<readium:");
+}
+
+const ids = readdirSync(FIXTURES_DIR, { withFileTypes: true })
+  .filter((e) => e.isDirectory())
+  .map((e) => e.name)
+  .filter((id) => {
+    try {
+      readFileSync(path.join(FIXTURES_DIR, id, "meta.json"), "utf-8");
+      return true;
+    } catch {
+      return false;
+    }
+  })
+  .sort();
+
+for (const id of ids) {
+  const dir = path.join(FIXTURES_DIR, id);
+  const gnd = JSON.parse(readFileSync(path.join(dir, "gnd.json"), "utf-8"));
+  const nodes = expectedTopLevel(gnd);
+  const rolesInTree = collectRoles(nodes);
+
+  const variantSpecs = [];
+
+  for (const role of skippableRoles) {
+    if (rolesInTree.has(role)) variantSpecs.push({ skip: [role] });
+  }
+
+  const hasAnnouncement = [...rolesInTree].some((role) => mod.defaultAnnouncements?.[role] !== undefined);
+  if (hasAnnouncement) variantSpecs.push({ contextualize: false });
+
+  if (containsPlaceholder(gnd)) variantSpecs.push({ interruptSentence: true });
+
+  if (id.startsWith("paragraph-") && (id.includes("language") || id.includes("multilingual"))) {
+    for (const language of ["never", "block", "inline"]) variantSpecs.push({ language });
+  }
+
+  const branches = {};
+  for (const format of ["plain", "ssml"]) {
+    const base = extractUtterances(nodes, { format });
+    const variants = [];
+    for (const options of variantSpecs) {
+      const utterances = extractUtterances(nodes, { format, ...options });
+      if (JSON.stringify(utterances) === JSON.stringify(base)) continue;
+      variants.push({ options, utterances });
+    }
+    branches[format] = variants.length > 0 ? { base, variants } : { base };
+  }
+
+  writeFileSync(path.join(dir, "utterances.json"), JSON.stringify(branches, null, 2) + "\n");
+}
+
+console.log(`Regenerated utterances.json for ${ids.length} fixtures.`);
diff --git a/src/gnd/converter.ts b/src/gnd/converter.ts
index a380ddc..ff3970f 100644
--- a/src/gnd/converter.ts
+++ b/src/gnd/converter.ts
@@ -606,17 +606,29 @@ export class Converter {
   }
 }
 
+// A DOM <body> only counts as real content when the input actually wrote
+// one — text/html parsing synthesizes a <body> around any fragment
+// regardless of what was passed in, and that synthesized wrapper was
+// never "in the input" just because the parser added it.
+const BODY_TAG_RE = /<body[\s>]/i;
+
 /**
- * Converts the children of an HTML or XHTML fragment or document's <body>
- * into Guided Navigation objects.
+ * Converts an HTML or XHTML fragment or document into Guided Navigation
+ * objects, reflecting exactly the input it's given: a real, author-written
+ * <body> becomes its own role: ["body"] node like any other element; a
+ * <body> synthesized only by text/html parsing around a bodyless fragment
+ * is not content and is skipped through; a bodyless XHTML fragment's root
+ * element is itself the content.
  */
 export function parseMarkup(input: string, mediaType?: GndMediaType): GndNode[] {
   const mt = mediaType ?? sniffMediaType(input);
   const doc = new DOMParser().parseFromString(input, mt);
-  const body = doc.querySelector("body");
-  const root = body ?? doc.documentElement;
-
   const converter = new Converter(mt === "application/xhtml+xml");
-  converter.convertChildren(root);
+  const body = doc.querySelector("body");
+  if (body && !BODY_TAG_RE.test(input)) {
+    converter.convertChildren(body);
+  } else {
+    converter.convert(body ?? doc.documentElement);
+  }
   return converter.result();
 }
diff --git a/src/gnd/makeGnd.ts b/src/gnd/makeGnd.ts
index 2728844..a8474da 100644
--- a/src/gnd/makeGnd.ts
+++ b/src/gnd/makeGnd.ts
@@ -9,8 +9,5 @@ export type { GndMediaType };
  * document, following https://github.com/readium/guided-navigation.
  */
 export function makeGnd(input: string, mediaType?: GndMediaType): GndDocument {
-  const children = parseMarkup(input, mediaType);
-  const body: GndDocument["guided"][number] = { role: ["body"] };
-  if (children.length > 0) body.children = children;
-  return { guided: [body] };
+  return { guided: parseMarkup(input, mediaType) };
 }
diff --git a/src/utterances/announcements.ts b/src/utterances/announcements.ts
index 7513221..077ceb1 100644
--- a/src/utterances/announcements.ts
+++ b/src/utterances/announcements.ts
@@ -1,12 +1,74 @@
 import type { Announcements } from "./types.js";
 
-// Default English announcement catalog. Expect this to grow considerably as
-// more roles gain contextualizing announcements (see `AnnouncementKey`);
-// callers can override or extend any subset of these keys via
+// Default English announcement catalog, one entry per GND role (see
+// `roles.md`: https://github.com/readium/guided-navigation/blob/main/roles.md).
+// See `Announcements` in `./types.js` for what a role's entry shape
+// (absent / a plain string / a `{start, end}` pair) means, and the rule
+// deciding which shape a given role gets, derived from that role's own
+// roles.md definition.
+//
+// `footnote` gets a `{start, end}` pair like any other collection/section
+// role — even though, unlike the others, it's read out of narrative order
+// (reached from a `noteref` elsewhere in the text, handled specially in
+// `extractUtterances.ts`), the announcement catalog itself doesn't need to
+// know that; it just says what to speak entering/leaving it.
+//
+// `glossref`, `biblioref`, `backlink`, and `noteref` itself have no entry:
+// they're references *to* a location, not a location of their own, and
+// (like `noteref`) their own visible text is a visual marker only.
+//
+// Callers can override or extend any subset of these keys via
 // `ExtractUtterancesOptions.announcements`, e.g. once localized catalogs
 // (Weblate-sourced) become available.
 export const defaultAnnouncements: Announcements = {
-  footnoteStart: "Start of the footnote.",
-  footnoteEnd: "End of the footnote.",
+  // Collections / sections with their own substructure — start/end pairs.
+  footnote: { start: "Start of the footnote.", end: "End of the footnote." },
+  part: { start: "Start of the part.", end: "End of the part." },
+  chapter: { start: "Start of the chapter.", end: "End of the chapter." },
+  prologue: { start: "Start of the prologue.", end: "End of the prologue." },
+  preface: { start: "Start of the preface.", end: "End of the preface." },
+  introduction: { start: "Start of the introduction.", end: "End of the introduction." },
+  conclusion: { start: "Start of the conclusion.", end: "End of the conclusion." },
+  epilogue: { start: "Start of the epilogue.", end: "End of the epilogue." },
+  afterword: { start: "Start of the afterword.", end: "End of the afterword." },
+  appendix: { start: "Start of the appendix.", end: "End of the appendix." },
+  acknowledgments: { start: "Start of the acknowledgments.", end: "End of the acknowledgments." },
+  endnotes: { start: "Start of the endnotes.", end: "End of the endnotes." },
+  glossary: { start: "Start of the glossary.", end: "End of the glossary." },
+  bibliography: { start: "Start of the bibliography.", end: "End of the bibliography." },
+  index: { start: "Start of the index.", end: "End of the index." },
+  toc: { start: "Start of the table of contents.", end: "End of the table of contents." },
+  pagelist: { start: "Start of the page list.", end: "End of the page list." },
+  landmarks: { start: "Start of the landmarks.", end: "End of the landmarks." },
+  loa: { start: "Start of the list of audio clips.", end: "End of the list of audio clips." },
+  loi: { start: "Start of the list of illustrations.", end: "End of the list of illustrations." },
+  lot: { start: "Start of the list of tables.", end: "End of the list of tables." },
+  lov: { start: "Start of the list of video clips.", end: "End of the list of video clips." },
+  qna: { start: "Start of the questions and answers.", end: "End of the questions and answers." },
+  table: { start: "Start of the table.", end: "End of the table." },
+  figure: { start: "Start of the figure.", end: "End of the figure." },
+  aside: { start: "Start of the aside.", end: "End of the aside." },
+  details: { start: "Start of the details.", end: "End of the details." },
+  credits: { start: "Start of the credits.", end: "End of the credits." },
+
+  // Single, self-contained pieces of content — one announcement each.
   pagebreak: "Pagebreak.",
+  heading1: "Heading level 1.",
+  heading2: "Heading level 2.",
+  heading3: "Heading level 3.",
+  heading4: "Heading level 4.",
+  heading5: "Heading level 5.",
+  heading6: "Heading level 6.",
+  subtitle: "Subtitle.",
+  epigraph: "Epigraph.",
+  abstract: "Abstract.",
+  colophon: "Colophon.",
+  dedication: "Dedication.",
+  cover: "Cover.",
+  errata: "Errata.",
+  notice: "Notice.",
+  example: "Example.",
+  tip: "Tip.",
+  pullquote: "Pull quote.",
+  credit: "Credit.",
 };
diff --git a/src/utterances/extractUtterances.ts b/src/utterances/extractUtterances.ts
index ce69f67..a714695 100644
--- a/src/utterances/extractUtterances.ts
+++ b/src/utterances/extractUtterances.ts
@@ -1,83 +1,202 @@
 import type { GndNode, GndRole } from "../gnd/types.js";
+import { ssmlTextEscape } from "../gnd/text.js";
 import type { ReadiumSpeechUtterance } from "../utterance.js";
 import { defaultAnnouncements } from "./announcements.js";
-import { resolveNodeText } from "./text.js";
-import type { Announcement, Announcements, ExtractUtterancesOptions } from "./types.js";
+import { stripLangTags } from "./language.js";
+import {
+  hasPlaceholder,
+  resolveNodeText,
+  splitOnPlaceholders,
+  stripSsmlTags,
+  type ResolvedNodeText,
+} from "./text.js";
+import { isAnnouncementPair, type Announcement, type Announcements, type ExtractUtterancesOptions } from "./types.js";
+
+interface WalkContext {
+  announcements: Announcements;
+  skip: ReadonlySet<GndRole>;
+  format: "plain" | "ssml";
+  contextualize: boolean;
+  interruptSentence: boolean;
+  language?: "never" | "block" | "inline";
+}
 
 function resolveAnnouncement(announcement: Announcement, params?: Record<string, string>): string {
   return typeof announcement === "function" ? announcement(params) : announcement;
 }
 
-function pushAnnouncement(
+// Every announcement/label utterance is sourced as plain text (the
+// announcement catalog, and a pagebreak/noteref's own visible label, never
+// carry markup of their own) — this formats that plain text per the
+// requested `format`, the same as any other utterance.
+function formatPlain(text: string, format: "plain" | "ssml"): ReadiumSpeechUtterance {
+  return format === "ssml" ? { ssml: ssmlTextEscape(text) } : { plain: text };
+}
+
+// Looks up `role`'s entry in the catalog and speaks the appropriate half
+// of it for this `phase`: a plain entry only has anything to say at
+// "before" (a single, self-contained announcement); a `{start, end}` pair
+// says its `start` at "before" and its `end` at "after". No-ops when the
+// role has no entry, or the shape doesn't have anything for this phase
+// (a plain entry at "after", or `contextualize: false`).
+function pushRoleAnnouncement(
   out: ReadiumSpeechUtterance[],
-  announcements: Announcements,
-  key: string,
+  ctx: WalkContext,
+  role: string,
+  phase: "before" | "after",
   params?: Record<string, string>,
 ): void {
-  const announcement = announcements[key];
-  if (announcement === undefined) return;
-  out.push({ plain: resolveAnnouncement(announcement, params) });
+  if (!ctx.contextualize) return;
+  const entry = ctx.announcements[role];
+  if (entry === undefined) return;
+  if (isAnnouncementPair(entry)) {
+    const announcement = phase === "before" ? entry.start : entry.end;
+    out.push(formatPlain(resolveAnnouncement(announcement, params), ctx.format));
+    return;
+  }
+  if (phase === "before") {
+    out.push(formatPlain(resolveAnnouncement(entry, params), ctx.format));
+  }
 }
 
 function isSkipped(roles: GndRole[], skip: ReadonlySet<GndRole>): boolean {
   return skip.size > 0 && roles.some((role) => skip.has(role));
 }
 
-function walk(
-  nodes: GndNode[],
+// Applies the required `format` option to an already-resolved node text,
+// synthesizing whichever field is missing: escaping `plain` into `ssml`
+// with no markup, or stripping `ssml`'s tags down to `plain`. Then applies
+// `language` — which only ever affects *this one node's own* inline
+// `<lang>` spans (never merges across sibling nodes, which each already
+// have their own separate utterance and stay that way regardless):
+//  - "inline" or omitted: no change — a node's own inline spans are
+//    honored as-is (already true of `ssml`; `plain` never had a way to
+//    show them anyway, so this is also the shape "block" reduces to for
+//    that format).
+//  - "block": ignore this node's own inline spans — unwrap any `<lang>`
+//    tags in its `ssml`, merging their text into the surrounding flow
+//    with no language of its own. Keeps this node's own `language`.
+//  - "never": same unwrapping as "block", and additionally drops this
+//    node's own `language` — the document is being treated as one
+//    language throughout, so nothing gets tagged at all.
+function applyFormat(
+  resolved: ResolvedNodeText,
+  format: "plain" | "ssml",
+  language: "never" | "block" | "inline" | undefined,
+): ReadiumSpeechUtterance {
+  const utterance: ReadiumSpeechUtterance = {};
+  if (resolved.language) utterance.language = resolved.language;
+  if (format === "ssml") {
+    utterance.ssml = resolved.ssml ?? ssmlTextEscape(resolved.plain ?? "");
+  } else {
+    utterance.plain = resolved.plain ?? stripSsmlTags(resolved.ssml ?? "");
+  }
+  if (language === "block" || language === "never") {
+    if (utterance.ssml) utterance.ssml = stripLangTags(utterance.ssml);
+    if (language === "never") delete utterance.language;
+  }
+  return utterance;
+}
+
+// `interruptSentence`: a node whose raw `ssml` embeds a placeholder always
+// got that placeholder because the converter decided `needSSML` (see
+// `flushText()` in `../gnd/converter.ts`), so the split point always comes
+// from the placeholder's position in `ssml` — regardless of the requested
+// `format`, which is only applied to each resulting fragment afterward.
+function emitInterrupted(
+  node: GndNode,
+  rawSsml: string,
   out: ReadiumSpeechUtterance[],
-  announcements: Announcements,
-  skip: ReadonlySet<GndRole>,
+  ctx: WalkContext,
 ): void {
-  for (const node of nodes) {
-    const roles = node.role ?? [];
-    if (isSkipped(roles, skip)) continue;
-
-    // A noteref's own visible text (e.g. "[1]") is a visual marker only,
-    // never spoken. Its footnote target is announced with a start/end pair
-    // around its normal extraction; any other kind of child is walked as-is.
-    if (roles.includes("noteref")) {
-      for (const child of node.children ?? []) {
-        const childRoles = child.role ?? [];
-        if (isSkipped(childRoles, skip)) continue;
-        if (childRoles.includes("footnote")) {
-          pushAnnouncement(out, announcements, "footnoteStart");
-          walk([child], out, announcements, skip);
-          pushAnnouncement(out, announcements, "footnoteEnd");
-        } else {
-          walk([child], out, announcements, skip);
-        }
-      }
+  const language = typeof node.text === "object" ? node.text.language : undefined;
+  const childrenById = new Map((node.children ?? []).map((child) => [child.id, child] as const));
+  for (const segment of splitOnPlaceholders(rawSsml)) {
+    if (segment.placeholderId !== undefined) {
+      const child = childrenById.get(segment.placeholderId);
+      if (child) walkNode(child, out, ctx);
       continue;
     }
+    if (!segment.ssml) continue;
+    const utterance: ReadiumSpeechUtterance = {};
+    if (language) utterance.language = language;
+    if (ctx.format === "ssml") utterance.ssml = segment.ssml;
+    else utterance.plain = stripSsmlTags(segment.ssml);
+    if (ctx.language === "block" || ctx.language === "never") {
+      if (utterance.ssml) utterance.ssml = stripLangTags(utterance.ssml);
+      if (ctx.language === "never") delete utterance.language;
+    }
+    out.push(utterance);
+  }
+}
+
+function walkNode(node: GndNode, out: ReadiumSpeechUtterance[], ctx: WalkContext): void {
+  const roles = node.role ?? [];
+  if (isSkipped(roles, ctx.skip)) return;
+
+  // A footnote node is always reached as a noteref's child (see the
+  // noteref branch below), which speaks its "footnote" announcement
+  // explicitly around walking it — excluded here so the generic loop
+  // doesn't speak it a second time. It's also commonly marked "aside"
+  // (DPUB-ARIA models it as a kind of aside), which would otherwise
+  // double-announce the same region redundantly, so that's excluded too.
+  const isFootnoteNode = roles.includes("footnote");
+  const announcedRoles = roles.filter(
+    (role) => !(isFootnoteNode && (role === "footnote" || role === "aside")),
+  );
 
-    const resolved = resolveNodeText(node.text);
-    if (resolved) {
-      // Only the "pagebreak" announcement itself is templated. The
-      // pagebreak's own label (from its `title`) is arbitrary author-supplied
-      // text — it might already read as "Page 5" or a roman numeral — so it's
-      // spoken as-is, not wrapped in a template that risks saying "page"
-      // twice or otherwise mangling it.
-      if (roles.includes("pagebreak")) {
-        pushAnnouncement(out, announcements, "pagebreak");
+  // Every role this node carries gets looked up in the announcement
+  // catalog and its "before" half spoken now, whatever shape that entry
+  // is (see `pushRoleAnnouncement` and `announcements.ts`) — a no-op for
+  // the vast majority of roles, which have no entry at all.
+  for (const role of announcedRoles) {
+    pushRoleAnnouncement(out, ctx, role, "before");
+  }
+
+  // A noteref's own visible text (e.g. "[1]") is a visual marker only,
+  // never spoken. Its footnote target is announced around its normal
+  // extraction (via the same catalog lookup as any other role); any other
+  // kind of child is walked as-is.
+  if (roles.includes("noteref")) {
+    for (const child of node.children ?? []) {
+      const childRoles = child.role ?? [];
+      if (isSkipped(childRoles, ctx.skip)) continue;
+      if (childRoles.includes("footnote")) {
+        pushRoleAnnouncement(out, ctx, "footnote", "before");
+        walk([child], out, ctx);
+        pushRoleAnnouncement(out, ctx, "footnote", "after");
+      } else {
+        walk([child], out, ctx);
       }
-      const utterance: ReadiumSpeechUtterance = {};
-      if (resolved.plain) utterance.plain = resolved.plain;
-      if (resolved.ssml) utterance.ssml = resolved.ssml;
-      if (resolved.language) utterance.language = resolved.language;
-      out.push(utterance);
     }
+  } else {
+    const rawSsml = typeof node.text === "object" ? node.text.ssml : undefined;
+    if (ctx.interruptSentence && rawSsml && hasPlaceholder(rawSsml)) {
+      emitInterrupted(node, rawSsml, out, ctx);
+    } else {
+      const resolved = resolveNodeText(node.text);
+      if (resolved) {
+        out.push(applyFormat(resolved, ctx.format, ctx.language));
+      }
+      if (node.children) walk(node.children, out, ctx);
+    }
+  }
 
-    if (node.children) walk(node.children, out, announcements, skip);
+  for (const role of announcedRoles) {
+    pushRoleAnnouncement(out, ctx, role, "after");
+  }
 
-    // A description is supplementary/elaborating content (e.g. an extended
-    // audio description), spoken after the primary content it describes.
-    if (node.description !== undefined) {
-      out.push({ plain: node.description });
-    }
+  // A description is supplementary/elaborating content (e.g. an extended
+  // audio description), spoken after the primary content it describes.
+  if (node.description !== undefined) {
+    out.push(formatPlain(node.description, ctx.format));
   }
 }
 
+function walk(nodes: GndNode[], out: ReadiumSpeechUtterance[], ctx: WalkContext): void {
+  for (const node of nodes) walkNode(node, out, ctx);
+}
+
 /**
  * Extracts an ordered list of read-aloud utterances from a Guided
  * Navigation node tree, following the patterns documented at
@@ -88,11 +207,17 @@ function walk(
  */
 export function extractUtterances(
   nodes: GndNode[],
-  options?: ExtractUtterancesOptions,
+  options: ExtractUtterancesOptions,
 ): ReadiumSpeechUtterance[] {
-  const announcements: Announcements = { ...defaultAnnouncements, ...options?.announcements };
-  const skip = new Set(options?.skip ?? []);
+  const ctx: WalkContext = {
+    announcements: { ...defaultAnnouncements, ...options.announcements },
+    skip: new Set(options.skip ?? []),
+    format: options.format,
+    contextualize: options.contextualize ?? true,
+    interruptSentence: options.interruptSentence ?? false,
+    language: options.language,
+  };
   const out: ReadiumSpeechUtterance[] = [];
-  walk(nodes, out, announcements, skip);
+  walk(nodes, out, ctx);
   return out;
 }
diff --git a/src/utterances/index.ts b/src/utterances/index.ts
index 67de521..fc9a1af 100644
--- a/src/utterances/index.ts
+++ b/src/utterances/index.ts
@@ -1,3 +1,11 @@
 export { extractUtterances } from "./extractUtterances.js";
 export { skippableRoles } from "./roles.js";
-export type { Announcement, AnnouncementKey, Announcements, ExtractUtterancesOptions } from "./types.js";
+export { defaultAnnouncements } from "./announcements.js";
+export type {
+  Announcement,
+  AnnouncementKey,
+  AnnouncementPair,
+  Announcements,
+  RoleAnnouncement,
+  ExtractUtterancesOptions,
+} from "./types.js";
diff --git a/src/utterances/language.ts b/src/utterances/language.ts
new file mode 100644
index 0000000..1a04af6
--- /dev/null
+++ b/src/utterances/language.ts
@@ -0,0 +1,9 @@
+// Removes `<lang xml:lang="...">...</lang>` wrapping from an SSML string,
+// keeping the inner text merged into the surrounding flow — for the
+// `language: "block"`/`"never"` extraction options, which ignore a node's
+// own inline language spans (only `"inline"`, or the default, honors them).
+const LANG_TAG_RE = /<lang xml:lang="[^"]*">([\s\S]*?)<\/lang>/g;
+
+export function stripLangTags(ssml: string): string {
+  return ssml.replace(LANG_TAG_RE, "$1");
+}
diff --git a/src/utterances/text.ts b/src/utterances/text.ts
index 9af335f..a2c9379 100644
--- a/src/utterances/text.ts
+++ b/src/utterances/text.ts
@@ -77,3 +77,57 @@ export function resolveNodeText(text: GndNode["text"]): ResolvedNodeText | undef
 
   return result.plain || result.ssml ? result : undefined;
 }
+
+// Strips every SSML tag (not just `<readium:...>` placeholders — `<lang>`,
+// `<emphasis>`, `<break/>`...) and unescapes the entities `ssmlTextEscape`
+// applies, for synthesizing a `plain` variant from a node that only
+// naturally has `ssml` (e.g. an inline language shift with no embedded
+// placeholder, so the GND converter never generated a `plain` variant for
+// it — see `converter.ts`'s `flushText()`).
+export function stripSsmlTags(ssml: string): string {
+  return ssml
+    .replace(/<[^>]+>/g, "")
+    .replace(/&lt;/g, "<")
+    .replace(/&gt;/g, ">")
+    .replace(/&amp;/g, "&")
+    .replace(/ {2,}/g, " ")
+    .trim();
+}
+
+export interface SsmlSegment {
+  // A run of ssml (may itself carry further tags, e.g. `<lang>`) between
+  // placeholders. Mutually exclusive with `placeholderId`.
+  ssml?: string;
+  // The `id` of a `<readium:TAG id="...">` placeholder at this position,
+  // linking to the sibling/child `GndNode` carrying that `id`.
+  placeholderId?: string;
+}
+
+// Matches a raw, unstripped `<readium:TAG id="...">` placeholder — the same
+// marker `stripPlaceholders` removes, but captured here (with its `id`) for
+// splitting the surrounding text apart instead of discarding it.
+const RAW_PLACEHOLDER_RE = /<readium:[a-zA-Z][\w-]*\s+id="([^"]*)"\s*\/>/g;
+
+export function hasPlaceholder(ssml: string): boolean {
+  return new RegExp(RAW_PLACEHOLDER_RE).test(ssml);
+}
+
+/**
+ * Splits a raw (pre-`stripPlaceholders`) SSML string on its embedded
+ * `<readium:TAG id="...">` placeholders, for `interruptSentence`: each
+ * placeholder becomes its own segment (resolved via the `GndNode` sharing
+ * its `id`) instead of being spoken after the whole enclosing text.
+ */
+export function splitOnPlaceholders(ssml: string): SsmlSegment[] {
+  const segments: SsmlSegment[] = [];
+  let lastIndex = 0;
+  for (const match of ssml.matchAll(RAW_PLACEHOLDER_RE)) {
+    const before = ssml.slice(lastIndex, match.index).trim();
+    if (before) segments.push({ ssml: before });
+    segments.push({ placeholderId: match[1] });
+    lastIndex = match.index! + match[0].length;
+  }
+  const after = ssml.slice(lastIndex).trim();
+  if (after) segments.push({ ssml: after });
+  return segments;
+}
diff --git a/src/utterances/types.ts b/src/utterances/types.ts
index 942ac24..43a13b8 100644
--- a/src/utterances/types.ts
+++ b/src/utterances/types.ts
@@ -3,17 +3,50 @@ import type { GndRole } from "../gnd/types.js";
 // Announcements are synthesized, navigational text the extractor adds to
 // contextualize an utterance (e.g. entering/leaving a footnote, a pagebreak
 // marker) — as opposed to content utterances, which speak text found in the
-// document itself. The catalog of announcement keys is expected to grow
-// substantially as more roles gain contextualizing announcements, so it's
-// kept as a plain string rather than a closed union — same rationale as
-// `GndRole` in `../gnd/types.js`.
+// document itself. The catalog is keyed by `GndRole` (kept as a plain
+// string rather than a closed union — same rationale as `GndRole` itself
+// in `../gnd/types.js` — since new roles gain an entry over time), and each
+// entry's own shape says what kind of announcement that role gets:
+//
+//  - absent (no key, or `undefined`): this role has nothing to announce.
+//  - a plain `Announcement`: a single, self-contained piece of content
+//    (a heading, a pagebreak label, a credit line...) gets spoken once,
+//    before its content.
+//  - `{ start, end }`: a collection or section with its own substructure
+//    (a chapter, a table, a table of contents...) gets a pair spoken
+//    before and after its content — a listener needs to be told when
+//    they've left a region like this, the same reason a footnote (read
+//    out of narrative order via a `noteref`) needs one.
+//
+// This is one translatable unit per role — plain strings or a nested
+// `{start, end}` object are both ordinary JSON a tool like Weblate
+// round-trips natively; there's no pair of unrelated flat keys for a
+// translator to know are connected.
 export type AnnouncementKey = string;
 
 export type Announcement = string | ((params?: Record<string, string>) => string);
 
-export type Announcements = Record<AnnouncementKey, Announcement>;
+export interface AnnouncementPair {
+  start: Announcement;
+  end: Announcement;
+}
+
+export type RoleAnnouncement = Announcement | AnnouncementPair;
+
+export function isAnnouncementPair(a: RoleAnnouncement): a is AnnouncementPair {
+  return typeof a === "object";
+}
+
+export type Announcements = Record<AnnouncementKey, RoleAnnouncement>;
 
 export interface ExtractUtterancesOptions {
+  // Every extraction is fully plain or fully SSML — required, not
+  // optional, and not a passthrough of "whatever the node happens to
+  // have". Forces exactly one field on every utterance, synthesizing it
+  // when a node only naturally has the other (escape plain into ssml with
+  // no markup; strip tags/placeholders from ssml into plain).
+  format: "plain" | "ssml";
+
   // A plain string index signature (not `Partial<Announcements>`): callers
   // can supply any subset of keys, known or new, without needing an
   // `| undefined` on every value.
@@ -24,4 +57,36 @@ export interface ExtractUtterancesOptions {
   // during playback. See `skippableRoles` for the roles.md-documented set.
   // Nothing is skipped by default (`[]`).
   skip?: GndRole[];
+
+  // Which language declarations in the *input* the extraction respects.
+  // This never merges separate sibling nodes into one utterance — each
+  // already has its own utterance and keeps it regardless — it only
+  // changes how *a single node's own* inline language spans (e.g.
+  // `<em lang="fr">`, embedded as SSML `<lang>` tags by the GND converter)
+  // are treated:
+  //  - "inline" or omitted: honor them as declared — a node's own inline
+  //    spans stay tagged in `ssml`; there's no plain-text equivalent, so
+  //    `format: "plain"` looks the same as "block" regardless.
+  //  - "block": ignore a node's own inline spans — merge their text into
+  //    the surrounding utterance untagged, keeping only that node's own
+  //    (block-level) `language`.
+  //  - "never": same merging as "block", and every utterance's `language`
+  //    is dropped entirely — the whole document is being treated as one
+  //    language, so nothing gets tagged at all.
+  language?: "never" | "block" | "inline";
+
+  // Whether a pagebreak/footnote placeholder that falls mid-sentence
+  // splits the enclosing utterance at that exact point (announcement/
+  // content spoken *during* the sentence) instead of after the whole
+  // sentence finishes (default, `false` — today's only behavior, for
+  // either `format`).
+  interruptSentence?: boolean;
+
+  // Master on/off switch for all synthesized contextualizing
+  // announcements (see `Announcements` for the growing per-role catalog).
+  // Default `true` (today's behavior). Distinct from `announcements`,
+  // which customizes *text*, not whether announcements happen at all;
+  // distinct from `skip`, which omits the underlying content too, not
+  // just its announcement.
+  contextualize?: boolean;
 }
diff --git a/test/gnd/fixtures.test.ts b/test/gnd/fixtures.test.ts
index e97a012..f883527 100644
--- a/test/gnd/fixtures.test.ts
+++ b/test/gnd/fixtures.test.ts
@@ -1,6 +1,6 @@
 import "./setup.js";
 import test from "ava";
-import { loadManifest, loadFixture } from "../testUtils.js";
+import { loadManifest, loadFixture, type UtterancesVariant } from "../testUtils.js";
 import { parseMarkup } from "../../src/gnd/converter.js";
 
 const manifest = loadManifest();
@@ -42,14 +42,8 @@ function expectedTopLevel(gnd: unknown): unknown[] {
   return [gnd];
 }
 
-// <body> is always the traversal root, never content in its own right, so
-// parseMarkup() never produces a "body"-rolebearing object for it to check
-// against — this fixture documents the expected role mapping but can't be
-// exercised through parseMarkup(); it's excluded from that check only.
-const excludedFromConvertCheck = new Set(["body-html-native"]);
-
 for (const entry of manifest) {
-  test(`fixture "${entry.id}": loads and has the expected shape`, (t) => {
+  test(`fixture "${entry.id}": loads and matches gnd.json`, (t) => {
     t.is(entry.dir, entry.id);
 
     const fixture = loadFixture(entry.id);
@@ -57,28 +51,31 @@ for (const entry of manifest) {
     t.is(fixture.meta.id, entry.id);
     t.is(fixture.meta.role, entry.role);
 
-    t.true(fixture.inputHtml.trim().length > 0, "input.html must not be empty");
+    t.true(fixture.inputHtml.trim().length > 0, "input file must not be empty");
 
     t.true(
       typeof fixture.gnd === "object" && fixture.gnd !== null,
       "gnd.json must parse to an object",
     );
 
-    t.true(Array.isArray(fixture.utterances), "utterances.json must parse to an array");
-    for (const utterance of fixture.utterances as Record<string, unknown>[]) {
-      t.true(typeof utterance === "object" && utterance !== null);
-      t.true(
-        typeof utterance.plain === "string" || typeof utterance.ssml === "string",
-        "each utterance needs a plain or ssml field",
-      );
+    for (const [format, branch] of Object.entries(fixture.utterances)) {
+      t.true(Array.isArray(branch.base), `utterances.json's "${format}" branch must have a base array`);
+      const lists = [
+        branch.base,
+        ...(branch.variants ?? []).map((v: UtterancesVariant) => v.utterances),
+      ];
+      for (const list of lists) {
+        for (const utterance of list as Record<string, unknown>[]) {
+          t.true(typeof utterance === "object" && utterance !== null);
+          t.true(
+            typeof utterance[format] === "string",
+            `each utterance in the "${format}" branch needs a ${format} field`,
+          );
+        }
+      }
     }
-  });
 
-  if (!excludedFromConvertCheck.has(entry.id)) {
-    test(`fixture "${entry.id}": parseMarkup matches gnd.json`, (t) => {
-      const fixture = loadFixture(entry.id);
-      const actual = parseMarkup(fixture.inputHtml);
-      t.deepEqual(sortKeysDeep(actual), sortKeysDeep(expectedTopLevel(fixture.gnd)));
-    });
-  }
+    const actual = parseMarkup(fixture.inputHtml);
+    t.deepEqual(sortKeysDeep(actual), sortKeysDeep(expectedTopLevel(fixture.gnd)));
+  });
 }
diff --git a/test/gnd/makeGnd.test.ts b/test/gnd/makeGnd.test.ts
new file mode 100644
index 0000000..4e5a085
--- /dev/null
+++ b/test/gnd/makeGnd.test.ts
@@ -0,0 +1,20 @@
+import "./setup.js";
+import test from "ava";
+import { makeGnd } from "../../src/gnd/makeGnd.js";
+import { parseMarkup } from "../../src/gnd/converter.js";
+
+test("makeGnd wraps parseMarkup's output as-is for a full document", (t) => {
+  const input = "<!DOCTYPE html><html><head><title>t</title></head><body><p>Hello.</p></body></html>";
+  t.deepEqual(makeGnd(input).guided, parseMarkup(input));
+});
+
+test("makeGnd wraps parseMarkup's output as-is for a bodyless fragment", (t) => {
+  const input = '<section epub:type="chapter" xml:lang="fr">Bonjour.</section>';
+  t.deepEqual(makeGnd(input, "application/xhtml+xml").guided, parseMarkup(input, "application/xhtml+xml"));
+});
+
+test("makeGnd never fabricates a body node for a bodyless fragment", (t) => {
+  const input = '<section epub:type="chapter" xml:lang="fr">Bonjour.</section>';
+  const doc = makeGnd(input, "application/xhtml+xml");
+  t.false(doc.guided.some((node) => node.role?.includes("body")));
+});
diff --git a/test/testUtils.ts b/test/testUtils.ts
index 8c30d5a..fcaabae 100644
--- a/test/testUtils.ts
+++ b/test/testUtils.ts
@@ -1,4 +1,4 @@
-import { readFileSync } from "fs";
+import { existsSync, readFileSync } from "fs";
 import { fileURLToPath } from "url";
 import { dirname, join } from "path";
 
@@ -20,12 +20,10 @@ export interface FixtureManifestEntry {
   dir: string;
   role: string;
   description: string;
-  skip?: string[];
   files: {
     input: string;
     gnd: string;
     utterances: string;
-    utterancesSkipped?: string;
   };
 }
 
@@ -36,15 +34,33 @@ export interface FixtureMeta {
   rolesCovered: string[];
   sourceRef: string;
   inputKind: "fragment" | "document";
-  skip?: string[];
+}
+
+// One extraction-options combination and its expected output, beyond the
+// format branch's own `base` (no extra options).
+export interface UtterancesVariant {
+  options: Record<string, unknown>;
+  utterances: unknown[];
+}
+
+export interface UtterancesBranch {
+  base: unknown[];
+  variants?: UtterancesVariant[];
+}
+
+// `utterances.json`'s shape: format is the fork (see fixtures/README.md),
+// each branch holding its own `base` plus whichever option variants that
+// fixture illustrates.
+export interface UtterancesFile {
+  plain: UtterancesBranch;
+  ssml: UtterancesBranch;
 }
 
 export interface LoadedFixture {
   meta: FixtureMeta;
   inputHtml: string;
   gnd: unknown;
-  utterances: unknown[];
-  utterancesSkipped?: unknown[];
+  utterances: UtterancesFile;
 }
 
 const fixturesDir = join(__dirname, "../fixtures");
@@ -62,11 +78,9 @@ export function loadManifest(): FixtureManifestEntry[] {
 export function loadFixture(id: string): LoadedFixture {
   const dir = join(fixturesDir, id);
   const meta: FixtureMeta = JSON.parse(readFileSync(join(dir, "meta.json"), "utf-8"));
-  const inputHtml = readFileSync(join(dir, "input.html"), "utf-8");
+  const inputFile = existsSync(join(dir, "input.xhtml")) ? "input.xhtml" : "input.html";
+  const inputHtml = readFileSync(join(dir, inputFile), "utf-8");
   const gnd = JSON.parse(readFileSync(join(dir, "gnd.json"), "utf-8"));
-  const utterances = JSON.parse(readFileSync(join(dir, "utterances.json"), "utf-8"));
-  const utterancesSkipped = meta.skip
-    ? JSON.parse(readFileSync(join(dir, "utterances-skipped.json"), "utf-8"))
-    : undefined;
-  return { meta, inputHtml, gnd, utterances, utterancesSkipped };
+  const utterances: UtterancesFile = JSON.parse(readFileSync(join(dir, "utterances.json"), "utf-8"));
+  return { meta, inputHtml, gnd, utterances };
 }
diff --git a/test/utterances/fixtures.test.ts b/test/utterances/fixtures.test.ts
index 2fd6875..77d81e8 100644
--- a/test/utterances/fixtures.test.ts
+++ b/test/utterances/fixtures.test.ts
@@ -20,19 +20,23 @@ function sortKeysDeep(value: unknown): unknown {
 }
 
 for (const entry of manifest) {
-  test(`fixture "${entry.id}": extractUtterances matches utterances.json`, (t) => {
-    const fixture = loadFixture(entry.id);
-    const gnd = parseMarkup(fixture.inputHtml);
-    const actual = extractUtterances(gnd);
-    t.deepEqual(sortKeysDeep(actual), sortKeysDeep(fixture.utterances));
-  });
+  const fixture = loadFixture(entry.id);
 
-  if (entry.skip) {
-    test(`fixture "${entry.id}": extractUtterances with skip matches utterances-skipped.json`, (t) => {
-      const fixture = loadFixture(entry.id);
+  for (const format of ["plain", "ssml"] as const) {
+    const branch = fixture.utterances[format];
+
+    test(`fixture "${entry.id}": extractUtterances matches utterances.json's "${format}" base`, (t) => {
       const gnd = parseMarkup(fixture.inputHtml);
-      const actual = extractUtterances(gnd, { skip: entry.skip });
-      t.deepEqual(sortKeysDeep(actual), sortKeysDeep(fixture.utterancesSkipped));
+      const actual = extractUtterances(gnd, { format });
+      t.deepEqual(sortKeysDeep(actual), sortKeysDeep(branch.base));
     });
+
+    for (const variant of branch.variants ?? []) {
+      test(`fixture "${entry.id}": extractUtterances matches utterances.json's "${format}" variant ${JSON.stringify(variant.options)}`, (t) => {
+        const gnd = parseMarkup(fixture.inputHtml);
+        const actual = extractUtterances(gnd, { format, ...variant.options });
+        t.deepEqual(sortKeysDeep(actual), sortKeysDeep(variant.utterances));
+      });
+    }
   }
 }