• Git

    Want to really, really understand Git?
    Let's write it! It's about 100 lines of straightforward Ruby code.
    The version we write is byte-compatible with Git itself — run `git log`, and our hand-authored commits will appear!

    Title Topic Duration Language Released
    Intro Git 1 min Ruby April 20, 2017 free
    Writing Bytes & Compression Git 13 min Ruby April 20, 2017
    Directories & Permissions Git 12 min Ruby May 4, 2017
    Subdirectories Git 10 min Ruby May 18, 2017
    Commits Git 13 min Ruby June 1, 2017
    Command line and Cache Git 8 min Ruby June 15, 2017
  • Matasano Crypto Challenges

    The Matasano Challenges are a wonderful way to learn about cryptography, but there's still so much to know before getting started!

    Title Topic Duration Language Released
    Wait, Which Data Structure Data structures 8 min Ruby, Python June 29, 2017
  • Merkle's Puzzles

    The first key exchange protocol, and the source of ideas behind the Blockchain.

    Title Topic Duration Language Released
    Merkle's Puzzles Crypto 11 min Ruby July 13, 2017
  • Quickcheck

    Title Topic Duration Language Released
    Property-based Testing Testing 7 min Ruby August 11, 2017
  • Rogue

    Title Topic Duration Language Released
    Terminal Graphics Games 9 min Ruby July 27, 2017
  • BSD Unix Shell Commands

    Fast-paced and condensed screencasts, each about writing a BSD shell command from start to finish.

    Title Topic Duration Language Released
    cat unix 6 min C May 12, 2017 free
    chmod unix 5 min C May 26, 2017
    echo unix 5 min C June 9, 2017
    mkdir unix 6 min C July 20, 2017 free
    Building paths for mkdir -p unix 6 min C August 4, 2017 free