Go in Action

Ch01

Go's Design Philosophy: Less Is More

Origin story, positioning vs C++/Java/Rust

Ch02

Development Environment and Toolchain

go build/test/vet/fmt/mod, project structure conventions

Ch03

Basic Types and Control Flow

Integers, floats, strings, booleans, zero-value design

Ch04

Functions, Closures and Defer

Multiple returns, closure pitfalls, defer ordering

Ch05

Composite Types: Arrays, Slices and Maps

Append growth behavior, nil slice vs empty slice

Ch06

Structs, Methods and Interfaces

Value vs pointer receivers, implicit interface implementation

Ch07

Error Handling: error, panic and recover

Error wrapping, errors.Is/As, sentinel errors

Ch08

Generics: From interface{} to Type Parameters

Type parameters, constraints, when to use generics

Ch09

Goroutines: Lightweight Concurrency

Creating and scheduling goroutines, leak detection

Ch10

Channels: Communication Between Goroutines

Buffered/unbuffered, select, fan-in/fan-out/pipeline patterns

Ch11

sync Package: Mutex, WaitGroup, Once, Pool

Mutexes, object pooling, sync.Map use cases

Ch12

Context: Cancellation, Timeout and Value Propagation

WithCancel/WithTimeout/WithValue best practices

Ch13

The Go Compiler: From Source to Binary

AST to SSA to machine code, escape analysis, inlining

Ch14

The GMP Scheduler: How Goroutines Run

G/M/P model, work stealing, preemptive scheduling

Ch15

Memory Allocator: tcmalloc Ideas in Go

mspan/mcache/mcentral/mheap, heap escape conditions

Ch16

Garbage Collection: Tri-Color Marking and Write Barriers

Tri-color invariant, GOGC tuning, soft memory limits

Ch17

Channel Internals: Send, Receive and Select

hchan struct, ring buffer, sudog wait queues

Ch18

Map Internals: Hash Table, Growth and Concurrency

hmap/bmap, incremental growth, sync.Map implementation

Ch19

Slice Internals: Growth Strategy and Memory Traps

SliceHeader, append growth formula, shared backing array traps

Ch20

Interface Internals: iface, eface and Type Assertion

Interface two-word value, itab cache, type assertion performance

Ch21

Reflect and Unsafe: Power and Risk

reflect.Type/Value, unsafe.Pointer rules

Ch22

CGo: The Cost of Dancing with C

CGo call overhead, memory management boundaries

Ch23

Network Model: netpoll and the epoll Wrapper

Go network I/O model, comparison with Nginx and Node.js

Ch24

Performance Analysis: pprof, trace and Benchmark

CPU/memory profiling, go tool trace, optimization patterns

Ch25

Project Architecture and Dependency Injection

Config to Server to Handler startup chain

Ch26

Web Services and Router Design

Gin framework, route groups, RESTful design

Ch27

Middleware Patterns

Rate limiting, logging, CORS, security header middleware

Ch28

Template Rendering and SEO

html/template engine, sitemap generation, JSON-LD

Ch29

Web Scraping: Concurrency and Rate Limiting

Worker pools, token bucket rate limiting, error retry

Ch30

Building CLI Tools

flag/cobra, progress reporting, subcommand design

Ch31

IP Lookup Service: Binary Protocol Parsing

IP2Location BIN parsing, CGo integration

Ch32

DNS Server: UDP Network Programming

DNS protocol, goroutine-per-request model

Ch33

WebSocket Real-Time Communication

Long connection management, heartbeat, broadcast patterns

Ch34

TLS Fingerprint Detection

Custom crypto/tls, JA3/JA4 fingerprinting

Ch35

Background Jobs and Graceful Shutdown

Timers, signal handling, graceful shutdown

Ch36

Build an HTTP Server from Scratch

net/http internals, TCP management, keep-alive

Ch37

Build a TCP Proxy

Bidirectional io.Copy, connection pooling, timeouts

Ch38

Build a Redis Client

RESP protocol parsing, connection pooling, pipelining

Ch39

Build a Message Queue

Persistence, pub/sub, consumer groups

Ch40

Build a Simple Container

Namespaces, cgroups, process isolation

Ch41

Build a Simple Database

B+Tree storage engine, WAL, MVCC basics

Ch42

Build an RPC Framework

Protobuf serialization, service registry, load balancing

Ch43

Build a Simple Shell

os/exec, pipes, signal handling

Ch44

Code Generation and Static Analysis

go/ast, go generate, custom linters

Ch45

Observability: Logging, Metrics and Tracing

zap logging, Prometheus metrics, OpenTelemetry

Ch46

Database Access: SQL, ORM and Connection Pool

database/sql, sqlx vs GORM, N+1 problem

Ch47

Authentication and Security

JWT, OAuth2, bcrypt, CSRF protection

Ch48

Build and Deploy

Multi-stage Docker, cross-compilation, systemd, CI/CD

Ch49

Calling LLM APIs: Streaming and Error Handling

Claude/OpenAI SDK, SSE streaming, token management

Ch50

Building AI Agents: Tool Use and Multi-Turn Dialogue

Function calling, tool dispatch, agent main loop

Ch51

Building an MCP Server

MCP protocol, JSON-RPC over stdio, Go implementation

Ch52

RAG Pipeline: Retrieval-Augmented Generation

Text chunking, embedding API, vector storage

Ch53

Vector Search Engine: Implementing HNSW from Scratch

HNSW algorithm in Go, approximate nearest neighbors