Yocto Layer Review

Yocto Layer Review

Use this skill to review layers and diagnose metadata visibility problems. Layer issues often look like recipe, provider, or package failures; prove whether BitBake sees the metadata first.

Required Evidence

Ask for or inspect:

conf/layer.conf
conf/bblayers.conf
bitbake-layers show-layers
bitbake-layers show-recipes <recipe>
bitbake-layers show-appends
bitbake-layers show-overlayed

Layer Checklist

Review:

BBPATH .= ":${LAYERDIR}"
BBFILES += "${LAYERDIR}/recipes-*/*/*.bb ${LAYERDIR}/recipes-*/*/*.bbappend"
BBFILE_COLLECTIONS += "mylayer"
BBFILE_PATTERN_mylayer = "^${LAYERDIR}/"
BBFILE_PRIORITY_mylayer = "6"
LAYERSERIES_COMPAT_mylayer = "scarthgap wrynose"
LAYERDEPENDS_mylayer = "core"

Check:

• collection name is unique and stable
• LAYERSERIES_COMPAT_* matches the target release
• required layers are declared with LAYERDEPENDS_*
• recipe and append globs cover intended files
• BBFILE_PRIORITY_* is not used to hide provider/version policy problems
• optional bbappends use BBFILES_DYNAMIC when the target layer may be absent
• .bbappend filename matches an existing recipe version or intentionally uses %

Common Problems

• layer is present in the tree but missing from bblayers.conf
• .bbappend silently not applied due to recipe version mismatch
• collection name in BBFILES_DYNAMIC does not match target layer collection
• layer priority causes a recipe to win unexpectedly
• vendor BSP layer pins an older release and rejects modern syntax
• dependency layer missing even though a recipe path exists locally

References

• Read references/official-doc-map.md for official layer docs.
• Read references/yocto-field-guide.md for layer and provider basics.
• Read references/migration.md for release compatibility checks.

Output

Answer with:

1. whether BitBake sees the layer and append
2. exact layer.conf or filename issue
3. metadata visibility command to prove it
4. minimal fix
5. validation command