The previous fix (docker_host: tcp://dind:2375) was wrong: act_runner
never passes DOCKER_HOST into job containers as an env var. It always
bind-mounts container.docker_host (read from ITS OWN filesystem) into
every job container as /var/run/docker.sock, and only recognizes
unix:// (or bare) paths -- a tcp:// value is silently treated as
unknown and falls back to a /var/run/docker.sock that doesn't exist in
the runner container, which is exactly the "no such file or directory"
error.
Expose dind's daemon over an additional unix socket on a volume shared
with the runner (dind-sock), and point docker_host at that shared path
so the bind-mount act_runner performs actually resolves to dind's real
socket. Verified by replicating act_runner's exact bind-mount pattern
against the running stack: `docker -H tcp://dind:2375 run -v
/dind-sock/docker.sock:/var/run/docker.sock ...` successfully ran
`docker info` and `docker build` inside a nested container.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01XFsukF6FzwBxJtRGzbt28F
docker_host: "-" was disabling docker access in job containers entirely,
so steps running `docker build`/`docker` directly had no daemon to talk
to. Point docker_host at the dind sibling and add a host-gateway entry
so the "dind" hostname resolves inside job containers, which run nested
on dind's own internal bridge network rather than the outer compose one.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01XFsukF6FzwBxJtRGzbt28F
Stable docker-compose setup for building Rust projects on Gitea Actions.
DinD-isolated daemon, built-in cache server, capacity=4 parallel jobs,
healthcheck-gated startup. Portable to other build machines via .env.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01HU4wDwdydNZpR3YkMiYYy8
nampdnandClaude Sonnet 5