Three complementary tweaks to close the gap sccache alone can't:
- CARGO_INCREMENTAL=0: reclaims the 17 incremental-mode cache misses
per run and prevents cargo from writing incremental fingerprints
that defeat sccache. Incremental mode is useless in CI anyway since
each run starts from scratch.
- actions/cache for ~/.cargo and target/: sidesteps sccache's
structural limits (proc-macro non-cacheables, clippy-vs-rustc
separate namespaces) by caching the whole build output keyed on
Cargo.lock. Also caches ~/.cargo/bin so the installed sccache
binary survives between runs.
- Drop the separate 'cargo build' step: 'cargo test --workspace'
builds everything anyway, so the standalone build was a full
redundant workspace compile pass.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
rob thijssen
15ded3a5bd
