Measured on 6154dc0: the three pre-commit jobs took 41-59s, of which 38-49s
was pre-commit installing hook environments and ~11s was an uncached pip.
The cache was not merely cold, it was miskeyed. pre-commit/action@v3.0.1
keys on hashFiles('.pre-commit-config.yaml') -- the repo ROOT's config --
but the hooks it installs come from the per-package config passed in
extra_args. Four different configs, one cache key: the three package jobs
raced to overwrite each other's hook sets, and editing a per-package config
never invalidated the key, so the restored cache was silently wrong rather
than missing. Three 68MB entries in the cache list are the symptom.
So the action is replaced with a direct `pre-commit run`, which keeps the
same --config/--all-files behaviour plus --show-diff-on-failure, wrapped in
an actions/cache keyed on the config that actually drives the install.
pre-commit is already an exact pin in each requirements.txt.
setup-python gains cache: pip keyed on each requirements.txt, for the test
jobs too.
The two crdt-sync workflows now list their own file in `paths`, which the
other four already did -- a workflow edit should re-run its own gate.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_019kMvSMtsVMB3d2uoZ56pbp
