Explore Go: Cryptography (Go 1.24 edition)

Have you ever wondered how passwords are stored securely? What makes a good password? How codes and ciphers are designed—and broken? Where random numbers come from, and what makes them random? What are the connections between lava lamps, space games, digital signatures, black holes, and Bitcoin? Let's find out.

Join Alice, Bob, Eve, and Mallory as we learn about the fundamental principles of cryptography and digital security, from brute force and blockchains to keyspaces and hashing. We'll build a cipher system in Go from scratch, with step-by-step instructions and code examples at each stage (also available on GitHub).

Starting with the simplest cipher imaginable, we'll gradually improve the system by attacking it, adding sophisticated features like block chaining, padding, digests, and authentication. Along the way, you'll develop a powerful intuitive understanding of ciphers and keys, what makes them strong (or weak), and how to use them securely.

We'll see how state-of-the-art modern algorithms like AES, SHA-256, Diffie-Hellman, and RSA work under the hood, and how to integrate them into real-world Go tools. This book is essential reading for all Go programmers who have to deal with encryption, authentication, and security… in other words, all of us!