Zephyr Justfile Usage

Use this skill to create or extend Justfiles for Zephyr applications, following the preferred patterns and conventions.

1) Start from the reference

• Use references/just-quick-reference.md as the default baseline.
• Pull missing details from references/just-manual.md only when needed.
• Use references/zephyr-justfile-template.just as the starting template for new apps.

2) Establish core settings

• Prefer set shell := ['zsh', '-uc'] and set unstable := true to match the template.
• Use require('west') to enforce tool availability.
• Derive app from source_dir() and board from west config build.board with a fallback.
• Keep variables at the top; expose knobs via env/vars, not long argument lists.

3) Default + discoverability

• Use a default listing recipe that formats the app name.
• Prefer just --list-heading to keep a consistent UI.

4) Zephyr build workflow

• Provide configure to set west config defaults (board, build dir format, pristine).
• Provide build, build_clean, and clean with build_dir derived from west config.
• Use board, snippet, target, and clean as overridable knobs.

5) Flash/run tooling

• Provide a flash recipe that depends on build.

6) Devicetree tooling (dtsh)

• Provide _dtsh guard + helpers: dts_tree, dts_ls, dts_cat, dtsh_out_html, dts_find.

7) Extend safely

• Group recipes by workflow stage: config, build, run, tools.
• Keep private helpers prefixed with _.
• Quote interpolations when values may include spaces.
• Use --justfile {{ source_file() }} for self-invocations.

References

• references/just-quick-reference.md — concise just patterns
• references/just-manual.md — baseline manual details
• references/zephyr-justfile-template.just — Zephyr app template