Unit 8 · Vibe coding with guardrails
git revert undoes one commit, not the latest
git revert <commit> undoes the one commit you name by adding a new commit that reverses it. It is not “undo the last thing”. Read the log, find the AI change, and revert that one, not your save point.
The mix-up
What people often think
“Revert undoes whatever happened most recently.”
What the tutor says
Revert undoes one specific commit, the one you pick. Read the commit messages and choose the AI change, not your save point.
How it works
Git tracks what changed, not whether it was a good idea. Only you, the diff and your tests can tell a good change from a bad one.
Working on a branch makes all of this calmer: a mistake there never reaches the version people use.
An example
git log --oneline
# a1b2c3d AI: rewrite search filter
# 9f8e7d6 Before AI edit
git revert a1b2c3dClose cousins of this mix-up
The tutor watches for these in the same lesson.
“Git can tell good changes from bad ones.”
Git tracks what changed, not whether it was a good idea. Only you, the diff and your tests can tell.
“Working straight on main is fine for small changes.”
Small AI changes are the ones that slip through. On a branch, a mistake never reaches the version people use.
Practise it with a tutor watching
Git as an undo button
Commit, branch, read the diff and revert, so a bad AI change costs you a minute instead of a day.
Free, no account needed.