build-image.yml is GitHub-only, so the image the Gitea runners are built FROM
could only be produced by GitHub. When GitHub Actions went unavailable on
2026-08-29 that circularity bit: the fix for openssl/jq missing from this image
— the absence that blocked v0.0.134 and v0.0.135 — could not be published on the
forge the project is moving to.
This publishes from the self-hosted runners through the in-cluster rootless
buildkitd, the path zegit images already use. buildah needing user namespaces
does not apply: buildkitd is a separate hardened workload and the job only
speaks to it over the network, so nothing is built inside the runner container.
Same contract as build-image.yml: a master push validates both arches and
publishes nothing, only an explicit dispatch names a tag and pushes, and a
dispatch without a package-write token fails loudly instead of reporting success
having pushed nothing.
The toolchain assertion is kept but done with buildkit rather than docker run,
which these runners lack: a stage FROM the published image whose RUN fails on a
missing tool, built natively for both arches. Verified it passes against an
image built from current master and fails with MISSING: openssl against the
deployed ci5.
The release tag gate parses the Control Plane quorum verdict and verifies its
Ed25519 DSSE signature by shelling out to jq and openssl. Neither is in this
image, and both call sites read cmd ... || { echo <security message>; exit 1; },
so command-not-found took the failure branch: the gate reported a valid, signed
approval first as "not a signed DSSE envelope" and then as "signature FAILED
verification". That blocked v0.0.134 and v0.0.135 on 2026-08-31 and pointed the
investigation at the Tag Request rather than at this image — the same shape as
the git-daemon gap already documented above the package list.
Also adds both to the toolchain assertion. That check already existed and still
missed them, because it only covers what someone thought to list; the comment
now says so, and says to extend it whenever a gate grows a shell dependency.
Verified by building this image and running the gate script inside it against
the live Control Plane: openssl 3.5.8, jq 1.8.1, and the v0.0.135 verdict
verifies and binds to its commit. The unpatched image fails the same script.
This image is a TOOLCHAIN, so "it built" is not the property worth checking —
"it still contains what the repo's gates shell out to" is.
It exists because the hand-built image had drifted from this Dockerfile: the
deployed ci3 carried gcc, musl-dev, python3 and py3-yaml, the Dockerfile did
not, and rebuilding from the Dockerfile silently dropped them. Gitea CI then
failed at "credentials-coverage: need python3" without reaching the tests at
all. Nothing in the pipeline objected, because every check asked whether the
image built, not what was in it.
Asserts python3 with a working yaml import, gcc, node, bash, make, curl, tar
and git-http-backend, on BOTH architectures — a package that resolves on amd64
but not arm64 would otherwise reach half the nodes unnoticed.
Verified the check can actually FAIL, which is the only property that makes it
worth having: against the bare forgejo/runner:12.11.1 it reports python3+yaml,
gcc, node and git-http-backend all MISSING; with the packages installed it
reports 3.12.14 and ok for the rest.
Publishing this image by hand kept hitting the same four walls — Cloudflare's
413, Docker parsing a bare MagicDNS name as a Docker Hub namespace, a PAT
missing write:package, and multi-arch. push-image.sh made that survivable;
this removes the manual step entirely.
It builds on GitHub rather than our own Gitea Actions because the runners
cannot build images: their labels are `ubuntu-latest:host` (host mode, no job
containers) and the container drops ALL capabilities with
allowPrivilegeEscalation:false, while rootless buildah needs newuidmap/user
namespaces for RUN steps. Building there would mean weakening the posture the
hardening established.
It publishes to ghcr.io rather than the Gitea registry because Cloudflare's
body cap is what caused the 413 in the first place, and because the cluster
already pulls zegit's own images from ghcr.io through an existing
github-registry-credentials pull secret — an established path rather than a
new one.
A master push validates that both arches still build but publishes nothing;
only an explicit dispatch names a tag and pushes, so a branch push cannot
silently mint a version. The final step reads the published index back and
fails if either architecture is absent, since a single-arch image under this
tag would CrashLoop on half the nodes.
Action SHAs match the pins zegit already uses, rather than introducing a
second set of versions to track.