For images you build yourself, a practical supply-chain loop is: build in CI, sign the digest, verify at admission. The lab uses Cosign (Sigstore), a private Zot registry at oci.this-is-fine.io, and Kyverno verifyImages so unsigned ZeroClaw pods do not start.

CI holds the private signing key; the cluster policy carries the matching public key.

Signing answers a simple question: did this image come from your build pipeline? Scanning for CVEs is still worth doing, but signature verification stops casual image substitution even when a tag name looks familiar.