Setup Go

Go Development Setup Skill

Purpose

Quickly set up and verify a Go development environment with all necessary tooling.

Workflow

Step 1: Verify Go Installation

go version

Expected: Go 1.20 or higher

If not installed:

❌ Go not found

Install Go:
- macOS: brew install go
- Linux: https://golang.org/doc/install
- Windows: https://golang.org/doc/install

After installing, verify: go version

Step 2: Check Project Structure

Verify go.mod exists:

ls go.mod

If doesn't exist:

No go.mod found. Initialize Go module:

go mod init <module-name>

Example:
go mod init github.com/username/project

Step 3: Install Dependencies

go mod download
go mod tidy

Explanation:

• go mod download: Downloads all dependencies
• go mod tidy: Removes unused dependencies, adds missing ones

Report:

✅ Dependencies installed

Direct dependencies: X
Indirect dependencies: Y
Go version: 1.21

Step 4: Setup golangci-lint

Check if installed:

golangci-lint version

If not installed:

# macOS/Linux
brew install golangci-lint

# Or using go install
go install github.com/golangci/golangci-lint/cmd/golangci-lint@latest

Create or verify .golangci.yml configuration:

linters:
  enable:
    - errcheck
    - gosimple
    - govet
    - ineffassign
    - staticcheck
    - unused
    - gofmt
    - goimports
    - revive
    - misspell
    - gocritic
    - unparam

linters-settings:
  errcheck:
    check-blank: true
  govet:
    check-shadowing: true
  revive:
    severity: warning

issues:
  exclude-use-default: false
  max-same-issues: 0

run:
  timeout: 5m
  tests: true

Run linter to verify:

golangci-lint run

Step 5: Setup Testing

Run existing tests:

go test ./... -v

Setup test coverage:

go test ./... -cover -coverprofile=coverage.out

View coverage:

go tool cover -func=coverage.out

Generate HTML coverage report:

go tool cover -html=coverage.out -o coverage.html

Report:

✅ Tests completed

Tests run: X
Tests passed: X
Tests failed: Y
Coverage: Z%

Step 6: Verify Build

go build ./...

Report:

✅ Build successful

All packages compile without errors.

If build fails:

❌ Build failed

[Show error output]

Common issues:
1. Missing dependencies: run 'go mod tidy'
2. Syntax errors: check the reported files
3. Import cycle: review package dependencies

Step 7: Setup Code Generation (if needed)

Check for generate directives:

grep -r "//go:generate" . --include="*.go"

If found, run:

go generate ./...

Step 8: Setup Makefile (Optional but Recommended)

Check if Makefile exists:

ls Makefile

If doesn't exist, create one:

.PHONY: build test lint fmt clean coverage

build:
	go build -v ./...

test:
	go test -v ./...

coverage:
	go test -coverprofile=coverage.out ./...
	go tool cover -func=coverage.out

lint:
	golangci-lint run

fmt:
	gofmt -s -w .
	goimports -w .

vet:
	go vet ./...

clean:
	go clean
	rm -f coverage.out coverage.html

all: fmt lint test build

Verify Makefile:

make all

Step 9: Setup Git Hooks (Optional)

Create pre-commit hook:

cat > .git/hooks/pre-commit << 'EOF'
#!/bin/bash
set -e

echo "Running pre-commit checks..."

# Format code
echo "Formatting code..."
gofmt -s -w .

# Run linter
echo "Running linter..."
golangci-lint run

# Run tests
echo "Running tests..."
go test ./...

echo "✅ Pre-commit checks passed"
EOF

chmod +x .git/hooks/pre-commit

Step 10: Summary Report

✅ Go Development Environment Setup Complete

Go version: 1.21.5
Module: github.com/user/project

Tooling:
✅ go mod tidy - Dependencies up to date
✅ golangci-lint - Configured and passing
✅ Tests - X tests passing (Y% coverage)
✅ Build - Successful
✅ Makefile - Created with common targets
✅ Git hooks - Pre-commit hook installed

Quick Commands:
- Build: make build OR go build ./...
- Test: make test OR go test ./...
- Lint: make lint OR golangci-lint run
- Format: make fmt OR gofmt -s -w .
- Coverage: make coverage

Ready to start development!

Common Go Commands Reference

Dependency Management

go mod init <module>        # Initialize new module
go mod download             # Download dependencies
go mod tidy                 # Clean up dependencies
go mod verify               # Verify dependencies
go mod vendor               # Vendor dependencies
go get <package>            # Add new dependency
go get -u <package>         # Update dependency

Building

go build                    # Build current package
go build ./...              # Build all packages
go build -o binary          # Build with custom name
go install                  # Build and install binary

Testing

go test ./...               # Run all tests
go test -v ./...            # Verbose output
go test -cover ./...        # With coverage
go test -race ./...         # Race condition detection
go test -bench=.            # Run benchmarks
go test -run TestName       # Run specific test

Code Quality

go fmt ./...                # Format code
goimports -w .              # Fix imports
go vet ./...                # Static analysis
golangci-lint run           # Comprehensive linting
go mod tidy                 # Clean dependencies

Debugging

go build -gcflags="-m"      # Escape analysis
go build -race              # Race detector
go test -cpuprofile cpu.prof  # CPU profiling
go test -memprofile mem.prof  # Memory profiling
go tool pprof cpu.prof      # Analyze profile

Troubleshooting

Issue: "go: command not found"

Solution: Go not installed or not in PATH

# macOS
brew install go

# Verify PATH includes Go
echo $PATH | grep go

Issue: "cannot find package"

Solution: Missing dependency

go mod download
go mod tidy

Issue: "import cycle not allowed"

Solution: Circular dependency between packages

• Review package dependencies
• Refactor to break the cycle
• Consider extracting shared code to new package

Issue: "golangci-lint: command not found"

Solution: Linter not installed

go install github.com/golangci/golangci-lint/cmd/golangci-lint@latest

# Ensure $GOPATH/bin is in PATH
export PATH=$PATH:$(go env GOPATH)/bin

Issue: Tests failing with "race condition detected"

Solution: Concurrent access to shared data

# Run with race detector to identify issue
go test -race ./...

# Fix by using proper synchronization (mutex, channels, etc.)

Best Practices

1. Always run go mod tidy before committing
2. Use golangci-lint for comprehensive linting
3. Enable race detector in CI/CD: go test -race ./...
4. Target 90%+ test coverage
5. Use goimports instead of gofmt (handles imports too)
6. Run go vet to catch common mistakes
7. Use Makefiles for consistent commands across team
8. Vendor dependencies for reproducible builds (optional)

Integration with Other Skills

This skill may be invoked by:

• quality-check - When checking Go code quality
• run-tests - When running Go tests