Skills

Bisect Regression

Find the exact commit that introduced a bug.

Install

npx skills add Archive228/loopkit --skill bisect-regression -g -a claude-code -y
Repository
Archive228/loopkit756
Category
Git and review
Updated
4mo ago
License
MIT
Context cost
Lightabout 143 tokens
Runs scripts
No, instructions only

What it does

Find the exact commit that introduced a bug. Use when something worked before and broke, and you don't know which change did it.

Bisect the Regression

  1. Find a known-good commit and a known-bad one. Confirm both by actually checking out and testing.
  2. git bisect start; git bisect bad <bad>; git bisect good <good>.
  3. At each step, run the SMALLEST test that distinguishes good from bad. Mark git bisect good/bad.
  4. When git names the first bad commit, read its diff. The bug is in those lines, don't guess elsewhere.
  5. git bisect reset. Report: the commit, the line, the one-sentence cause. Automate it: git bisect run ./repro.sh if you have a script that exits non-zero on the bug.

More in Git and review