The launcher, npm shim, and `impeccable install` all resolve the engine
binary for the pinned ENGINE_VERSION, so a skill/CLI release or a rust-swap
merge published ahead of the engine release + platform packages dead-ends
every install path. Add a mechanical guard:
- scripts/check-engine-release.mjs: verifies all five dist binaries +
.sha256 and the five @impeccable/cli-<os>-<arch> npm platform packages
exist for the pinned ENGINE_VERSION; names missing assets, exits non-zero.
Honors IMPECCABLE_DOWNLOAD_BASE.
- release.mjs: hard-fails release:skill and release:cli when assets are
missing; extension is exempt (vendored WASM detector, no engine exec).
- CI engine-release-ready job: runs the check, continue-on-error with a
loud ::warning until the first engine release exists (flip to false then).
- CLAUDE.md Releases: documents the enforced ordering.
Prepared with AI assistance (Claude Code).
