The compatibility gate started the pinned 2.25.5 source build inside the same
step that runs the three measured lanes, so `make -j$(nproc)` competed with two
container lanes whose wall clock is container starts, not Git. A boundary case
that costs ~1.5s stretched past Vitest's 30s timeout and failed the job.
Build the binary in its own step before the matrix, and pull both images before
any lane starts so a lazy pull cannot stall whichever test its sibling is timing.
None of these change what CI checks — they remove work the runners
repeated on every PR.
- install-node-dependencies installed with --no-frozen-lockfile, so every
job re-resolved the graph against the registry to recompute what the
lockfile already pins. Measured at ~62 MB of packument metadata per job;
the pnpm store cache does not cover the metadata cache, so this was paid
~39 times per run. The `git diff` guard that made the re-resolution
redundant stays.
- --ignore-scripts leaves node-pty with no build/Release, so
ensure-native-runtime node-gyp-compiled it in every job asking for a
runtime. Cache the build under an ABI-bound key (runtime, resolved Node
version, node-pty patch) with no restore-keys, since a partial match is
exactly the mismatched build that would be recompiled anyway.
- The four fetch-depth: 0 checkouts pulled full history including every
historical blob (blobs are ~89% of this repo's pack). They only need the
commit graph for a merge-base diff, so fetch them blobless. Measured
30-43s each today versus 8s for the shallow checkouts. One of them,
e2e-paths, gates the entire E2E chain.
- E2E jobs ordered setup-node before pnpm, which meant setup-node could not
find the store and no E2E job cached dependencies at all. Reorder and
cache; this sits on the critical path in both the build job and each
shard.
- git_compatibility rebuilt Git 2.25.5 from a pinned tarball on every PR.
Cache the build; the sha256 assertion still guards the miss path.
- typecheck ran three independent tsc passes back to back and discarded the
.tsbuildinfo each project already emits. Run them concurrently and cache
the incremental state.
- package (windows) built the electron-vite targets serially via
build:release. Use a :parallel variant that overlaps them, matching what
the Linux package job already packages and smoke-tests from.
Contract tests cover each new cache's ordering and key so none of them can
silently start serving a stale or ABI-mismatched artifact.
Neil
Brennan Benson