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diff review
The human job is the diff, not the file. If you have not seen what moved, you do not merge.
What is diff review?
Diff review reads the contrast: new branches, deleted tests, drive-by formatting. Cheaper than the whole file, harder to fool with “it runs.”
Why does diff review matter when vibe coding?
Vibe coding turns the human from author into editor. Editors do not rewrite the book. They read the change. Skip the diff and you gave the merge key to the model.
How do you do diff review?
Three checks per diff: did scope escape this slice, did tests get weaker, did unrelated files move. One yes, send it back.
How do you ask a model for diff review?
After edits, summarise the diff: which files, why. No drive-by formatting. Changes outside (scope) go in another turn.
What goes wrong with diff review?
Checking only that tests are green. Green can mean an assertion was deleted. A missing test in the diff is worse than a red bar.