Go Tutorial

A practical tutorial to get you productive with Go.

Who This Is For

• Developers with experience in other languages
• Those wanting to learn Go for backend development, CLI tools, or cloud-native applications
• Anyone looking for a practical, example-driven guide

Contents

Fundamentals

1. Introduction - What is Go, installation, first program
2. Basics - Variables, types, operators, strings
3. Control Flow - If, for, switch, defer
4. Functions - Functions, closures, methods
5. Collections - Arrays, slices, maps

Object-Oriented Go

6. Structs & Methods - Structs, methods, embedding
7. Interfaces - Interfaces, polymorphism, type assertions

Core Concepts

8. Error Handling - Error patterns, wrapping, custom errors
9. Concurrency - Goroutines, channels, sync package

Ecosystem

10. Packages & Modules - Project structure, dependencies
11. Testing - Unit tests, benchmarks, fuzzing
12. Standard Library - Essential stdlib packages

Mastery

13. Best Practices - Idioms, patterns, anti-patterns

How to Use This Tutorial

1. Read sequentially for a complete learning path
2. Jump to specific topics if you need a reference
3. Type out the examples - don't just read them
4. Build something after each section

Quick Reference

Essential Commands

# Create a new project
mkdir myproject && cd myproject
go mod init github.com/username/myproject

# Run a program
go run main.go

# Build an executable
go build

# Run tests
go test ./...

# Format code
go fmt ./...

# Manage dependencies
go mod tidy

Hello World

package main

import "fmt"

func main() {
    fmt.Println("Hello, World!")
}

Common Patterns

// Error handling
result, err := doSomething()
if err != nil {
    return fmt.Errorf("doing something: %w", err)
}

// Goroutine with channel
ch := make(chan string)
go func() {
    ch <- "result"
}()
result := <-ch

// HTTP handler
http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
    fmt.Fprint(w, "Hello!")
})
http.ListenAndServe(":8080", nil)

Learning Path Suggestions

Backend Developer (2-3 days)

1. Fundamentals (chapters 1-5)
2. Structs & Interfaces (6-7)
3. Error Handling (8)
4. Standard Library (12) - focus on net/http, encoding/json
5. Build a REST API

DevOps/CLI Developer (2-3 days)

1. Fundamentals (chapters 1-5)
2. Error Handling (8)
3. Packages & Modules (10)
4. Standard Library (12) - focus on os, flag, exec
5. Build a CLI tool

Systems Programmer (1 week)

1. All fundamentals (1-9)
2. Deep dive into Concurrency (9)
3. Standard Library (12) - focus on sync, io, os
4. Build a concurrent data processor

Additional Resources

• Official Go Documentation
• Go by Example
• Effective Go
• Go Playground - Try Go in the browser
• Go Wiki

Go Version

This tutorial is written for Go 1.21+ and covers features up to Go 1.22.