Go’s net/http package is fantastic—but sometimes you want to see what’s really happening under the hood.

In this article, we’ll build a tiny HTTP/1.1 server from scratch, using only:

• net — for TCP sockets
• bufio — for buffered I/O

No net/http, no handler interface, no magic.

You’ll learn:

• How HTTP/1.1 requests look on the wire
• How to parse the request line and headers
• How to build a minimal response (status line, headers, body)
• How to handle multiple connections with goroutines
• A tiny router for different paths

This is not production code—it’s a learning tool. But it’s a great way to deeply understand HTTP.

Go’s net/http package is deceptively simple on the surface—just call http.ListenAndServe() and pass a handler. But beneath its minimal API lies a highly optimized, battle-tested, and beautifully engineered HTTP runtime.

This article explores the internal architecture, concurrency model, lifecycle, request handling flow, connection reuse, transport behaviors, and performance strategies that make net/http one of Go’s most iconic packages.

This is a true deep dive—use it to understand how Go’s HTTP stack really works under the hood.

The net package is the foundation of all network programming in Go.
Everything — from HTTP servers to gRPC, Redis clients, DNS resolvers, and low-level TCP/UDP tools — ultimately relies on Go’s networking stack built around the net package.

This article provides a deep, practical, and complete exploration of net with clear explanations and runnable examples.

1. Why the net Package Matters

Go’s networking model is:

• Simple – Uses familiar Unix-style sockets and file descriptors.
• Cross-platform – Same code works on Linux, macOS, Windows.
• Concurrent by design – Each connection can be handled by a goroutine.
• Powerful – TCP, UDP, Unix domain sockets, DNS, interfaces, IPs, CIDR tools, etc.

Higher-level packages rely on it: