A lockless npm project (e.g. glance, 2015) resolved an unpinned transitive range to the
latest major ([email protected] -> mime@4, which dropped .lookup()), so the built app crashed
serving files -- a build-reproducibility defect, not an app or agent fault. The executor
now, for the npm-install (no-lock) case only and only when .git is present, resolves
dependencies as of the checkout's HEAD commit date via `npm install --before <date>`,
giving era-appropriate, compatible versions. npm ci (lockfile present) is untouched, and
any git/date failure falls back to plain install. demo.py also recognizes
npm-shrinkwrap.json as a lock for the ci-vs-install choice.
Tests: executor + smoke 75 passed, demo 107 passed; ruff clean; mypy clean on executor.py.
Executor-side change -> image rebuild required.
Co-Authored-By: Claude Opus 4.8 <[email protected]>
