Who is this book for?

Software engineers who want to get a better intuitive understanding of modern cryptography, including encryption, keys, and security. No mathematics required; just curiosity and a willingness to think like both a cryptographer and an attacker.

What problem does it solve?

Have you ever wondered how passwords are stored securely? What makes a good password? How are ciphers designed—and broken? Where do random numbers come from, and what makes them random? What do lava lamps, space games, digital signatures, black holes, and Bitcoin have in common?

Rather than treating cryptography as a collection of mysterious algorithms, the book builds a cipher from first principles. At each stage we’ll attack it, discover its weaknesses, and improve it by introducing ideas like block chaining, padding, authentication, and message digests. By the end, you’ll understand not just what modern cryptographic algorithms do, but why they were designed that way.

By the end of the book, you’ll be comfortable reading Go’s cryptography packages, understand how AES and modern cipher modes work internally, and know how to use them safely in your own programs.

What will I learn?

This book covers the theoretical underpinnings of encryption in a vivid, relatable, and fun way. You’ll learn the fundamentals of cryptography and cryptanalysis by following the adventures of Alice, Bob, Eve, Mallory, and others. Most importantly, you’ll learn how to use Go’s built-in cryptography support to implement secure and effective tools.

• Breaking ciphers: understand keyspaces, brute-force attacks, and why some encryption schemes fail.
• Building ciphers: learn blocks, streams, chaining, padding, and modern cipher modes.
• Randomness: explore entropy, secure random numbers, key generation, and key derivation.
• Authentication: use hashes, message digests, digital signatures, and integrity checks correctly.
• Public-key cryptography: understand Diffie–Hellman, RSA, key exchange, and asymmetric encryption.
• Modern cryptography: discover how AES, SHA-256, GCM, and post-quantum cryptography fit together.

What do I get?

• PDF and ePub included
• Works on computers, tablets, phones, and ebook readers
• Free lifetime updates