golang-continuous-integration

What this skill does

**Persona:** You are a Go DevOps engineer. You treat CI as a quality gate — every pipeline decision is weighed against build speed, signal reliability, and security posture.

**Modes:**

- **Setup** — adding CI to a project for the first time: start with the Quick Reference table, then generate workflows in this order: test → lint → security → release. Prefer the latest stable major version for each GitHub Action.
- **Improve** — auditing or extending an existing pipeline: read current workflow files first, identify gaps against the Quick Reference table, then propose targeted additions without duplicating existing steps.

**Dependencies:**

- goreleaser: `go install github.com/goreleaser/goreleaser/v2@latest`
- gh: `brew install gh`

# Go Continuous Integration

Set up production-grade CI/CD pipelines for Go projects using GitHub Actions.

## Action Versions

The versions in the examples below are reference versions that may be outdated. GitHub Actions release frequently — the current major version for each action (`actions/checkout`, `actions/setup-go`, `golangci/golangci-lint-action`, `codecov/codecov-action`, `goreleaser/goreleaser-action`, etc.) may differ from what is shown here.

## Quick Reference

| Stage         | Tool                        | Purpose                       |
| ------------- | --------------------------- | ----------------------------- |
| **Test**      | `go test -race`             | Unit + race detection         |
| **Coverage**  | `codecov/codecov-action`    | Coverage reporting            |
| **Lint**      | `golangci-lint`             | Comprehensive linting         |
| **Vet**       | `go vet`                    | Built-in static analysis      |
| **SAST**      | `gosec`, `CodeQL`, `Bearer` | Security static analysis      |
| **Vuln scan** | `govulncheck`               | Known vulnerability detection |
| **Docker**    | `docker/build-push-action`  | Multi-platform image builds   |
| **Deps**      | Dependabot / Renovate       | Automated dependency updates  |
| **Release**   | GoReleaser                  | Automated binary releases     |
| **AI Review** | Claude Code / Copilot       | AI-powered PR review          |

---

## Testing

`.github/workflows/test.yml` — see [test.yml](./assets/test.yml)

Adapt the Go version matrix to match `go.mod`:

```
go 1.23   → matrix: ["1.23", "1.24", "1.25", "1.26", "stable"]
go 1.24   → matrix: ["1.24", "1.25", "1.26", "stable"]
go 1.25   → matrix: ["1.25", "1.26", "stable"]
go 1.26   → matrix: ["1.26", "stable"]
```

Use `fail-fast: false` so a failure on one Go version doesn't cancel the others.

Test flags:

- `-race`: CI MUST run tests with the `-race` flag (catches data races — undefined behavior in Go)
- `-shuffle=on`: Randomize test order to catch inter-test dependencies
- `-coverprofile`: Generate coverage data
- `git diff --exit-code`: Fails if `go mod tidy` changes anything

### Coverage Configuration

CI SHOULD enforce code coverage thresholds. Configure thresholds in `codecov.yml` at the repo root — see [codecov.yml](./assets/codecov.yml)

---

## Integration Tests

`.github/workflows/integration.yml` — see [integration.yml](./assets/integration.yml)

Use `-count=1` to disable test caching — cached results can hide flaky service interactions.

---

## Linting

`golangci-lint` MUST be run in CI on every PR. `.github/workflows/lint.yml` — see [lint.yml](./assets/lint.yml)

### golangci-lint Configuration

Create `.golangci.yml` at the root of the project. See the `samber/cc-skills-golang@golang-lint` skill for the recommended configuration.

---

## Security & SAST

`.github/workflows/security.yml` — see [security.yml](./assets/security.yml)

CI MUST run `govulncheck`. It only reports vulnerabilities in code paths your project actually calls — unlike generic CVE scanners. CodeQL results appear in the repository's Security tab. Bearer is good at detecting sensitive data flow issues.

### CodeQL Configuration

Create `.github/codeql/codeql-config.yml` to use the extended security query suite — see [codeql-config.yml](./assets/codeql-config.yml)

Available query suites:

- **default**: Standard security queries
- **security-extended**: Extra security queries with slightly lower precision
- **security-and-quality**: Security queries plus maintainability and reliability checks

### Container Image Scanning

If the project produces Docker images, Trivy container scanning is included in the Docker workflow — see [docker.yml](./assets/docker.yml)

---

## Dependency Management

### Dependabot

`.github/dependabot.yml` — see [dependabot.yml](./assets/dependabot.yml)

Minor/patch updates are grouped into a single PR. Major updates get individual PRs since they may have breaking changes.

#### Auto-Merge for Dependabot

`.github/workflows/dependabot-auto-merge.yml` — see [dependabot-auto-merge.yml](./assets/dependabot-auto-merge.yml)

> **Security warning:** This workflow requires `contents: write` and `pull-requests: write` — these are elevated permissions that allow merging PRs and modifying repository content. The `if: github.actor == 'dependabot[bot]'` guard restricts execution to Dependabot only. Do not remove this guard. Note that `github.actor` checks are not fully spoof-proof — **branch protection rules are the real safety net**. Ensure branch protection is configured (see [Repository Security Settings](#repository-security-settings)) with required status checks and required approvals so that auto-merge only succeeds after all checks pass, regardless of who triggered the workflow.

### Renovate (alternative)

Renovate is a more mature and configurable alternative to Dependabot. It supports automerge natively, grouping, scheduling, regex managers, and monorepo-aware updates. If Dependabot feels too limited, Renovate is the go-to choice.

Install the [Renovate GitHub App](https://github.com/apps/renovate), then create `renovate.json` at the repo root — see [renovate.json](./assets/renovate.json)

Key advantages over Dependabot:

- **`gomodTidy`**: Automatically runs `go mod tidy` after updates
- **Native automerge**: No separate workflow needed
- **Better grouping**: More flexible rules for grouping PRs
- **Regex managers**: Can update versions in Dockerfiles, Makefiles, etc.
- **Monorepo support**: Handles Go workspaces and multi-module repos

---

## Release Automation

GoReleaser automates binary builds, checksums, and GitHub Releases. The configuration varies significantly depending on the project type.

### Release Workflow

`.github/workflows/release.yml` — see [release.yml](./assets/release.yml)

> **Security warning:** This workflow requires `contents: write` to create GitHub Releases. It is restricted to tag pushes (`tags: ["v*"]`) so it cannot be triggered by pull requests or branch pushes. Only users with push access to the repository can create tags.

### GoReleaser for CLI/Programs

Programs need cross-compiled binaries, archives, and optionally Docker images.

`.goreleaser.yml` — see [goreleaser-cli.yml](./assets/goreleaser-cli.yml)

### GoReleaser for Libraries

Libraries don't produce binaries — they only need a GitHub Release with a changelog. Use a minimal config that skips the build.

`.goreleaser.yml` — see [goreleaser-lib.yml](./assets/goreleaser-lib.yml)

For libraries, you may not even need GoReleaser — a simple GitHub Release created via the UI or `gh release create` is often sufficient.

### GoReleaser for Monorepos / Multi-Binary

When a repository contains multiple commands (e.g., `cmd/api/`, `cmd/worker/`).

`.goreleaser.yml` — see [goreleaser-monorepo.yml](./assets/goreleaser-monorepo.yml)

### Docker Build & Push

For projects that produce Docker images. This workflow builds multi-platform images, generates SBOM and provenance attestations, pushes to both GitHub Container Registry (GHCR) and Docker Hub, and includes Trivy container scanning.

`.github/workflows/docker.yml` — see [docker.yml](./assets/docker.yml)

> **Security warning:** Permissi