Preserve canonical_fingerprint unchanged as the pre-tailor artifact-set digest; embed it in ReleaseManifest and compute release identity once over canonical validated manifest serialization.
Stage, fsync, verify, and atomically publish immutable releases under the XDG user-data root while refusing mutation of an existing digest directory.
Serialize concurrent install and publish operations with a store lock; quarantine interrupted or corrupt staging directories with receipts.
Verify every selected release on read; require user-only local permissions and authenticated signatures for the first and every later remote fetch.
Verification
Write failing positive, negative, interruption, concurrency, and idempotency cases before implementation.
Pin the consumer-visible outcome through the real CLI/runtime entry point.
Run focused pytest and the owning runtime self-test with a 150-second test timeout.
Run python -m scripts.harness_dist verify --root . when distributed artifact classification changes.