Go Development Patterns

When to Use

Go services/CLIs, job scheduling, Docker API, LDAP/AD clients, resilience patterns, test suites.

Required Workflow

For reviews, invoke related skills: security-audit (OWASP), enterprise-readiness (OpenSSF/SLSA), github-project (branch protection). A review is NOT complete until all are executed.

Core Principles

Type Safety

• Avoid: interface{} (use any), sync.Map, scattered type assertions, reflection
• Prefer: Generics [T any], errors.AsType[T] (Go 1.26), concrete types
• Run go fix ./... after upgrades

Consistency

• One pattern per problem domain
• Match existing codebase patterns
• Refactor holistically or not at all
• Config precedence: defaults < config file < env vars < flags

Testing

• Build tags isolate test tiers: unit (default), integration, e2e
• Always use t.Parallel(), t.Helper(), table-driven subtests
• Use log/slog directly -- never wrap it in custom Logger interfaces

Conventions

• Errors: lowercase, no punctuation (errors.New("invalid input"))
• Naming: ID, URL, HTTP (not Id, Url, Http)
• Error wrapping: fmt.Errorf("failed to process: %w", err)

References

Git hooks: ls lefthook.yml 2>/dev/null && lefthook install || echo "Add lefthook — see references/lefthook-template.md"

Load as needed:

Reference	Purpose
references/architecture.md	Package structure, config management, middleware chains
references/logging.md	Structured logging with log/slog, migration from logrus
references/cron-scheduling.md	go-cron patterns: named jobs, runtime updates, context, resilience
references/resilience.md	Retry logic, graceful shutdown, context propagation
references/docker.md	Docker client patterns, buffer pooling
references/ldap.md	LDAP/Active Directory integration
references/testing.md	Test strategies, build tags, table-driven tests
references/linting.md	golangci-lint v2, staticcheck, code quality
references/api-design.md	Bitmask options, functional options, builders
references/fuzz-testing.md	Go fuzzing patterns, security seeds
references/mutation-testing.md	Gremlins configuration, test quality measurement
references/makefile.md	Standard Makefile interface for CI/CD
references/modernization.md	Go 1.26 modernizers, go fix, errors.AsType[T], wg.Go()
references/lefthook-template.md	Ready-to-use lefthook.yml for Go project git hooks
references/reusable-workflows.md	Reusable Actions workflow callers, permission propagation, release-gate outputs
references/single-build-release.md	Single-build release: cross-compile once, reuse for release+container

Quality Gates

Run before completing any review:

golangci-lint run --timeout 5m    # Linting
go vet ./...                       # Static analysis
staticcheck ./...                  # Additional checks
govulncheck ./...                  # Vulnerability scan
go test -race ./...                # Race detection

Stdlib Vulnerability Fixes

When govulncheck reports stdlib vulnerabilities: check fix version via vuln.go.dev, update go X.Y.Z in go.mod, run go mod tidy. Use PR branches for repos with branch protection.

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Contributing: Submit improvements to https://github.com/netresearch/go-development-skill