go

name	go
description	Google's official Go style guide. Covers gofmt formatting, naming conventions, error handling, interfaces, concurrency patterns, and package organization. Enforces idiomatic Go code with short variable names and explicit error checks.

Google Go Style Guide

Official Google Go coding standards for idiomatic, maintainable code.

Golden Rules

1. Run gofmt before commit — formatting is non-negotiable
2. Short variable names in small scopes — i, err, ctx
3. Error handling, not exceptions — check every error
4. Interfaces for abstraction — accept interfaces, return structs
5. Defer for cleanup — ensure resources are released
6. Explicit is better — avoid magic, prefer clarity
7. Package names: lowercase, single word — no underscores

Quick Reference

Naming Conventions

Element	Convention	Example
Packages	lowercase	package user
Files	lowercase_underscore	user_service.go
Types	UpperCamelCase	UserService
Functions/Methods	UpperCamelCase (exported)	GetUser
Functions/Methods	lowerCamelCase (unexported)	getUserByID
Variables	lowerCamelCase	userCount
Constants	UpperCamelCase or UPPER_SNAKE	MaxRetries
Interfaces	UpperCamelCase + -er suffix	Reader, Writer

Variables

// ✓ CORRECT - short names in small scopes
for i := 0; i < 10; i++ {
    // ...
}

// ✓ CORRECT - descriptive names in larger scopes
func ProcessUserData(userRepository UserRepository) error {
    // ...
}

// ✗ INCORRECT - unnecessarily long
for index := 0; index < 10; index++ {
    // ...
}

Error Handling

// ✓ CORRECT - check every error
user, err := getUser(id)
if err != nil {
    return nil, fmt.Errorf("failed to get user: %w", err)
}

// ✗ INCORRECT - ignoring errors
user, _ := getUser(id)

Functions

// ✓ CORRECT - multiple return values
func GetUser(id int) (*User, error) {
    // ...
}

// ✓ CORRECT - named return values for clarity
func ParseConfig(path string) (cfg *Config, err error) {
    // ...
}

Interfaces

// ✓ CORRECT - small, focused interfaces
type Reader interface {
    Read(p []byte) (n int, err error)
}

// ✓ CORRECT - accept interfaces, return structs
func ProcessData(r Reader) (*Result, error) {
    // ...
}

Defer

// ✓ CORRECT - defer for cleanup
func ReadFile(path string) ([]byte, error) {
    f, err := os.Open(path)
    if err != nil {
        return nil, err
    }
    defer f.Close()
    
    return io.ReadAll(f)
}

Goroutines and Channels

// ✓ CORRECT - use context for cancellation
func ProcessItems(ctx context.Context, items []Item) error {
    for _, item := range items {
        select {
        case <-ctx.Done():
            return ctx.Err()
        default:
            if err := process(item); err != nil {
                return err
            }
        }
    }
    return nil
}

// ✓ CORRECT - buffered channels when appropriate
results := make(chan Result, len(items))

Package Organization

// ✓ CORRECT - package comment
// Package user provides user management functionality.
package user

// ✓ CORRECT - group imports
import (
    "context"
    "fmt"
    
    "github.com/pkg/errors"
    
    "myapp/internal/db"
)

Common Mistakes

Mistake	Correct Approach
Ignoring errors	Check every error
Long variable names in loops	Use short names (i, j)
Panic for normal errors	Return errors
Naked returns	Use explicit returns
Not running gofmt	Always format code
Underscores in package names	Use single lowercase word

When to Use This Guide

• Writing new Go code
• Refactoring existing Go
• Code reviews
• Setting up linting rules (golangci-lint)
• Onboarding new team members

Install

npx skills add testdino-hq/google-styleguides-skills/go

Full Guide

See go.md for complete details, examples, and edge cases.