gx-act

gx-act — local GitHub Actions

Use whenever a change touches code that would trigger CI on GitHub. Run the workflows locally with act first; only push the branch when the local run is green, then squash-merge the PR on GitHub.

When to invoke

• Before gx pr open / gx pr sync / gx branch finish --via-pr.
• Before re-pushing after a CI failure.
• When iterating on .github/workflows/*.yml itself.

Install act

act requires Docker (or Podman). Check the binary:

command -v act || echo "act not installed"

Install one way:

# Linux/macOS via the upstream installer
curl -fsSL https://raw.githubusercontent.com/nektos/act/master/install.sh | bash -s -- -b "$HOME/.local/bin"

# macOS via Homebrew
brew install act

# Arch
sudo pacman -S act

# Or use the GitHub CLI extension
gh extension install https://github.com/nektos/gh-act

Upstream: https://github.com/nektos/act

Quick commands

# List jobs the local runner would execute for the push event
act -l

# Run the default push workflows (what GitHub runs on a normal push)
act push

# Run a specific event
act pull_request
act workflow_dispatch -W .github/workflows/release.yml

# Run a single job
act -j test

# Pin a runner image (medium is the act default; large matches real GH closer)
act -P ubuntu-latest=catthehacker/ubuntu:act-latest

# Pass secrets / env without committing them
act -s GITHUB_TOKEN="$GITHUB_TOKEN" --env-file .env.act

# Reuse containers between runs (faster iteration)
act --reuse

Workflow (local CI → squash-merge on GitHub)

1. Implement the change in the agent worktree.
2. act -l to confirm which jobs will fire for the event you care about.
3. act push (or the specific event/job) until it is green locally.
4. gx branch finish --branch "<agent-branch>" --base main --via-pr --wait-for-merge --cleanup.
   • Or gx pr open then gx pr sync --auto-merge --merge-strategy squash for explicit PR control.
5. On GitHub: squash-merge once the remote run mirrors the local one.

Notes

• act does not reproduce GitHub-hosted services exactly (no real secrets, different runner image, no concurrency groups). Treat a green act run as a strong signal, not a proof — the remote run is still authoritative.
• Keep act config in .actrc at the repo root so every agent uses the same runner image.
• If a workflow uses GITHUB_TOKEN for API calls, pass a PAT via -s GITHUB_TOKEN=...; do not commit it.
• Add .actrc, .cache/act, and any act-specific event payloads to .gitignore if they appear.