Understudyguided code replays
Local runtimeChoose a replay

Four kata replays / easy to medium

Learn from real history: Understudy drops you at the commit before a meaningful change and asks you to rebuild it yourself.

Practice small algorithm changes in your own editor. Tests decide when the behavior is right.

How it worksA short loop around a real change.
  1. 1

    Pick a replay. Start from real history.

  2. 2

    Open your copy. Work in your own editor.

  3. 3

    Prove it. Let the tests decide.

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