diff --git a/CHANGELOG.md b/CHANGELOG.md
index 0100803..05679ac 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,6 +7,8 @@ adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
 ## [Unreleased]
 
+## [0.4.0] - 2026-06-14
+
 ### Added
 
 - **Browser playground at `/afm/playground/`** — Solid + Vite frontend
diff --git a/Cargo.lock b/Cargo.lock
index a47943a..08d02fe 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -19,7 +19,7 @@ checksum = "320119579fcad9c21884f5c4861d16174d0e06250625266f50fe6898340abefa"
 
 [[package]]
 name = "afm-cli"
-version = "0.3.0"
+version = "0.4.0"
 dependencies = [
  "afm-markdown",
  "aozora",
@@ -32,7 +32,7 @@ dependencies = [
 
 [[package]]
 name = "afm-markdown"
-version = "0.3.0"
+version = "0.4.0"
 dependencies = [
  "afm-markdown-test-support",
  "aozora",
@@ -50,14 +50,14 @@ dependencies = [
 
 [[package]]
 name = "afm-markdown-test-support"
-version = "0.3.0"
+version = "0.4.0"
 dependencies = [
  "aozora",
 ]
 
 [[package]]
 name = "afm-wasm"
-version = "0.3.0"
+version = "0.4.0"
 dependencies = [
  "afm-markdown",
  "aozora",
@@ -152,8 +152,8 @@ checksum = "7f202df86484c868dbad7eaa557ef785d5c66295e41b460ef922eca0723b842c"
 
 [[package]]
 name = "aozora"
-version = "0.3.0"
-source = "git+https://github.com/P4suta/aozora.git?rev=27ad4a79e93786a3b0364b6ed9ed941b8554721e#27ad4a79e93786a3b0364b6ed9ed941b8554721e"
+version = "0.4.0"
+source = "git+https://github.com/P4suta/aozora.git?rev=df0f64b1a42897030d4b7d0129fb7564e070ab73#df0f64b1a42897030d4b7d0129fb7564e070ab73"
 dependencies = [
  "aozora-encoding",
  "aozora-pipeline",
@@ -168,8 +168,8 @@ dependencies = [
 
 [[package]]
 name = "aozora-encoding"
-version = "0.3.0"
-source = "git+https://github.com/P4suta/aozora.git?rev=27ad4a79e93786a3b0364b6ed9ed941b8554721e#27ad4a79e93786a3b0364b6ed9ed941b8554721e"
+version = "0.4.0"
+source = "git+https://github.com/P4suta/aozora.git?rev=df0f64b1a42897030d4b7d0129fb7564e070ab73#df0f64b1a42897030d4b7d0129fb7564e070ab73"
 dependencies = [
  "encoding_rs",
  "miette",
@@ -180,8 +180,8 @@ dependencies = [
 
 [[package]]
 name = "aozora-pipeline"
-version = "0.3.0"
-source = "git+https://github.com/P4suta/aozora.git?rev=27ad4a79e93786a3b0364b6ed9ed941b8554721e#27ad4a79e93786a3b0364b6ed9ed941b8554721e"
+version = "0.4.0"
+source = "git+https://github.com/P4suta/aozora.git?rev=df0f64b1a42897030d4b7d0129fb7564e070ab73#df0f64b1a42897030d4b7d0129fb7564e070ab73"
 dependencies = [
  "aho-corasick",
  "aozora-encoding",
@@ -199,16 +199,16 @@ dependencies = [
 
 [[package]]
 name = "aozora-proptest"
-version = "0.3.0"
-source = "git+https://github.com/P4suta/aozora.git?rev=27ad4a79e93786a3b0364b6ed9ed941b8554721e#27ad4a79e93786a3b0364b6ed9ed941b8554721e"
+version = "0.4.0"
+source = "git+https://github.com/P4suta/aozora.git?rev=df0f64b1a42897030d4b7d0129fb7564e070ab73#df0f64b1a42897030d4b7d0129fb7564e070ab73"
 dependencies = [
  "proptest",
 ]
 
 [[package]]
 name = "aozora-render"
-version = "0.3.0"
-source = "git+https://github.com/P4suta/aozora.git?rev=27ad4a79e93786a3b0364b6ed9ed941b8554721e#27ad4a79e93786a3b0364b6ed9ed941b8554721e"
+version = "0.4.0"
+source = "git+https://github.com/P4suta/aozora.git?rev=df0f64b1a42897030d4b7d0129fb7564e070ab73#df0f64b1a42897030d4b7d0129fb7564e070ab73"
 dependencies = [
  "aozora-pipeline",
  "aozora-spec",
@@ -218,8 +218,8 @@ dependencies = [
 
 [[package]]
 name = "aozora-scan"
-version = "0.3.0"
-source = "git+https://github.com/P4suta/aozora.git?rev=27ad4a79e93786a3b0364b6ed9ed941b8554721e#27ad4a79e93786a3b0364b6ed9ed941b8554721e"
+version = "0.4.0"
+source = "git+https://github.com/P4suta/aozora.git?rev=df0f64b1a42897030d4b7d0129fb7564e070ab73#df0f64b1a42897030d4b7d0129fb7564e070ab73"
 dependencies = [
  "aho-corasick",
  "aozora-spec",
@@ -228,8 +228,8 @@ dependencies = [
 
 [[package]]
 name = "aozora-spec"
-version = "0.3.0"
-source = "git+https://github.com/P4suta/aozora.git?rev=27ad4a79e93786a3b0364b6ed9ed941b8554721e#27ad4a79e93786a3b0364b6ed9ed941b8554721e"
+version = "0.4.0"
+source = "git+https://github.com/P4suta/aozora.git?rev=df0f64b1a42897030d4b7d0129fb7564e070ab73#df0f64b1a42897030d4b7d0129fb7564e070ab73"
 dependencies = [
  "miette",
  "thiserror",
@@ -237,8 +237,8 @@ dependencies = [
 
 [[package]]
 name = "aozora-syntax"
-version = "0.3.0"
-source = "git+https://github.com/P4suta/aozora.git?rev=27ad4a79e93786a3b0364b6ed9ed941b8554721e#27ad4a79e93786a3b0364b6ed9ed941b8554721e"
+version = "0.4.0"
+source = "git+https://github.com/P4suta/aozora.git?rev=df0f64b1a42897030d4b7d0129fb7564e070ab73#df0f64b1a42897030d4b7d0129fb7564e070ab73"
 dependencies = [
  "aozora-encoding",
  "aozora-spec",
@@ -251,8 +251,8 @@ dependencies = [
 
 [[package]]
 name = "aozora-veb"
-version = "0.3.0"
-source = "git+https://github.com/P4suta/aozora.git?rev=27ad4a79e93786a3b0364b6ed9ed941b8554721e#27ad4a79e93786a3b0364b6ed9ed941b8554721e"
+version = "0.4.0"
+source = "git+https://github.com/P4suta/aozora.git?rev=df0f64b1a42897030d4b7d0129fb7564e070ab73#df0f64b1a42897030d4b7d0129fb7564e070ab73"
 
 [[package]]
 name = "autocfg"
@@ -1917,7 +1917,7 @@ dependencies = [
 
 [[package]]
 name = "xtask"
-version = "0.3.0"
+version = "0.4.0"
 dependencies = [
  "afm-markdown",
  "anyhow",
diff --git a/Cargo.toml b/Cargo.toml
index 74d77ff..54df387 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -14,7 +14,7 @@ members = [
 exclude = ["upstream/comrak", "crates/afm-book"]
 
 [workspace.package]
-version       = "0.3.0"
+version       = "0.4.0"
 edition       = "2024"
 rust-version  = "1.95.0"
 license       = "Apache-2.0 OR MIT"
@@ -157,10 +157,10 @@ redundant_pub_crate     = "allow"
 
 [workspace.dependencies]
 # Internal crate (the Markdown-integration layer that lives in this repo)
-afm-markdown = { version = "0.3.0", path = "crates/afm-markdown" }
+afm-markdown = { version = "0.4.0", path = "crates/afm-markdown" }
 # Internal test-only crate. `publish = false` so the version is purely
 # a cargo-deny placeholder; the real coupling is the workspace path.
-afm-markdown-test-support = { version = "0.3.0", path = "crates/afm-markdown-test-support" }
+afm-markdown-test-support = { version = "0.4.0", path = "crates/afm-markdown-test-support" }
 
 # Sibling repo aozora — pure 青空文庫記法 parser. afm depends on the
 # single umbrella `aozora` crate (its designated front door), NOT the
@@ -180,7 +180,7 @@ afm-markdown-test-support = { version = "0.3.0", path = "crates/afm-markdown-tes
 # `default-features = false` keeps cst / query / wire / proptest / schema
 # out of the build graph; the dev-only proptest generators come in via
 # the `proptest` feature on the afm-markdown dev-dependency.
-aozora = { version = "0.3.0", git = "https://github.com/P4suta/aozora.git", rev = "27ad4a79e93786a3b0364b6ed9ed941b8554721e", default-features = false }
+aozora = { version = "0.4.0", git = "https://github.com/P4suta/aozora.git", rev = "df0f64b1a42897030d4b7d0129fb7564e070ab73", default-features = false }
 
 # comrak vendored fork (path, not crates.io).
 # `default-features = false` drops the comrak CLI (`cli` / `syntect` / `bon`)
diff --git a/crates/afm-markdown/fuzz/Cargo.toml b/crates/afm-markdown/fuzz/Cargo.toml
index 057ad59..5d72bf5 100644
--- a/crates/afm-markdown/fuzz/Cargo.toml
+++ b/crates/afm-markdown/fuzz/Cargo.toml
@@ -16,7 +16,7 @@ afm-markdown-test-support = { path = "../../afm-markdown-test-support" }
 # parent workspace's `aozora` (a loose `branch = "main"` could drift from
 # the rev afm builds against). `aozora::encoding::decode_sjis` is the
 # umbrella path for the SJIS decoder the sjis_decode target fuzzes.
-aozora                    = { version = "0.3.0", git = "https://github.com/P4suta/aozora.git", rev = "c91b31d8a14f131413d3528aaf41bc1b240beca1", default-features = false }
+aozora                    = { version = "0.4.0", git = "https://github.com/P4suta/aozora.git", rev = "df0f64b1a42897030d4b7d0129fb7564e070ab73", default-features = false }
 
 # Prevent this crate from joining the afm workspace.
 # Each fuzz target needs libfuzzer-sys (nightly-gated), which the