The compiled-in extension registry: six example-class namespaces, one deprecated, one product-owned critical entry with an authored schema pin. Registry content is a code release; there is no runtime registry file — drift between shipped code and shipped registry is unrepresentable.
Governance
The governance-canonical SOURCE is spec/registry/registry.json,
bound to both compiled twins (the Elixir module and the TypeScript
verifier's registry) and the corpus index by the registry-equality
gate: all four carriers must carry the same canonical digest.
Lifecycle
reserved → active → deprecated → retired. Promotion to critical requires a protocol revision increment; demotion does not; a retired namespace is never reused. Deprecated entries keep their artifacts verifiable with a typed notice.
Pinning
The registry's digest is bound into the corpus index but not into
artifact digests — an artifact stays verifiable against a registry
that legitimately gained entries after it was produced. Hosts wanting
pinning use build_identities.