When Claude changes several files and your tests fail, a git diff only tells you what changed. It does not tell you which step did it. Time Machine is a Claude Code mod that records each step in order, with a snapshot of your files, so you can go back to any one.
Here's what it does, how to install it, the catches, and a prompt to start with.
What it does
- Records every tool call (each edit and command) on a timeline, with a snapshot of your files after it.
- Keeps the snapshots in its own hidden git store, so nothing is written to your own .git.
- /tm why points at the edit that broke a failing test run.
- /tm restore <n> puts your files back to step n (it shows a dry run first), and /tm branch <n> tries another path from that step.
- /tm compare puts two runs side by side, and /tm rerun repeats a step with the same input.
Free, for your email
Get the full setup steps + the copy-paste setup prompt
The rest of this guide (3 more sections, 1 copy-paste prompt) opens right here. The setup prompt, one paste into Claude that sets it all up, comes by email only. Use your real address.
Unlocks: Step 1: install it · The catches · Sources
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