Operator decision on PR #81: no CI job may reach a privileged daemon. The act runner is untouched.
- platform/buildkit (+ clusters/base/buildkit.yaml): moby/buildkit v0.34.1-rootless pinned by
digest, uid 1000, not privileged; caps drop ALL + SETUID/SETGID, seccomp/AppArmor Unconfined,
read-only rootfs (each measured under podman). cert-manager CA + server/client certs, ClusterIP
:1234, default-deny with ingress only from the act-runner pod (DinD masquerades jobs to it).
No Kyverno exception: every applied policy matches app-namespace=true only.
- Each Containerfile names its shipped stage and ends in a `verify` stage holding every former
`docker run` assertion (uid 65532, RUN --network=none, writable-path inventory standing in for
the read-only rootfs). The old `&& echo` checks that could never fail are real assertions now.
- images.sh drives buildkitd with a pinned buildx (sha256-checked) via bake; PRs build verify
targets with agent-runner FROM the in-run toolbox (target: context); main verifies, then pushes.
Fails loudly when the builder secrets are absent or buildkitd is unreachable.
- infra/gitea/buildkit-client-secret.sh copies the client cert into Actions secrets.
Co-Authored-By: Claude Opus 5.5 <[email protected]>