📍 v2.0 modernization roadmap / where we left off (start here)

[jonfroehlich]

A single front door for the v2.0 Arduino modernization work, so it's easy to pick back up. Status as of 2026-06-26.

⏭️ Immediate next action

Merge PR #15 (sketch-board-targeting). It is green on all 4 board jobs and mergeable. It:

• assigns the correct board per sketch via sketch.yaml (closes Assign correct board per sketch via sketch.yaml #11),
• adds compile-CI matrix jobs for AVR/Leonardo/SAMD/nRF52,
• marks the i2s-mic+mp3 sketch legacy, and
• comments each sketch.yaml + documents the convention in CLAUDE.md.

Open decision before merging: merge as-is, or first fold in #16 (grow CI coverage) so it lands as one "board targeting + coverage" change. Either is fine — #16 is comfortably its own PR. Default recommendation: merge #15 now, do #16 separately.

🔭 Backlog, in suggested priority order

1. Grow compile-CI coverage to remaining green sketches + untracked boards #16 — Grow compile-CI coverage to remaining green sketches + untracked boards (UnoR4WiFi, CPX, rest of nRF52840). Natural follow-on to Assign correct board per sketch via sketch.yaml; gate in CI (#11) #15. Quick win: run the full arduino-cli sweep, add the green ones to the Uno job.
2. Triage & migrate ESP32 sketches for Arduino core v3.x (lesson-aware) #12 — Triage & migrate ESP32 sketches for core v3.x (lesson-aware). Includes the Tone32.hpp → native tone() migration. Check the physcomp lesson before migrating vs. marking legacy.
3. v2.0: fundamental review of all sketch code + comments #13 — Fundamental review of all sketch code + comments (the big v2.0 pass).
4. Update the headers to each .ino to reference textbook, as relevant #9 — Update .ino headers to reference the textbook. Overlaps v2.0: fundamental review of all sketch code + comments #13 — decide whether to fold Update the headers to each .ino to reference textbook, as relevant #9 into v2.0: fundamental review of all sketch code + comments #13 or keep it as a focused headers-only task.
5. CI link-check for textbook lesson URLs in sketch headers #14 — CI link-check for textbook lesson URLs in sketch headers.
6. AnalogGraphMultipleInputs.ino - e-Ink port #7 — AnalogGraphMultipleInputs e-Ink port (older, narrow enhancement).

✅ Recently completed (for context)

• Assign correct board per sketch via sketch.yaml #11 board targeting (PR Assign correct board per sketch via sketch.yaml; gate in CI (#11) #15, pending merge)
• Move MakeabilityLab_Arduino_Library into its own repo #6 closed — MakeabilityLab library now lives in its own repo (makelab-arduino-lib)
• Compile-check CI established with a START-GREEN policy (.github/workflows/compile-sketches.yml)
• Legacy ESP32/Tone + i2s-mic sketches marked & excluded (docs/legacy-sketches.md)

🔑 Key context / conventions (don't relearn the hard way)

• Sketch-header template: docs/sketch-header-template.md; compile-checked copy in templates/SketchTemplate/.
• Legacy policy: banner in .ino + list in docs/legacy-sketches.md + skip in CI. Check the lesson before deciding migrate-vs-legacy.
• CI gotcha: arduino/compile-sketches does not read sketch.yaml — mixed-board folders must be listed per-sketch under the right matrix job.
• arduino-cli at C:\Program Files\Arduino CLI\arduino-cli.exe (may not be on PATH).