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repro
Steps that make the bug happen on a clean machine. Without a repro, the model is guessing.
What is repro?
A repro is a short, ordered list: start here, click this, see that. Better: a failing test. Best: a command that exits non-zero.
Why does repro matter when vibe coding?
“It’s broken” plus a screenshot of the whole desktop is how you burn five turns. A repro lets the model run, fail, patch, run. That is TDD with a bug as the spec.
How do you do repro?
Before asking for a fix, write the repro. If you cannot, that is the first task: make it fail on command. Then the model may touch code.
How do you ask a model for repro?
Do not guess. Here is the repro: (steps or command). Make a failing test from it first, then fix. If you cannot reproduce, stop and say so.
What goes wrong with repro?
A repro that needs your laptop, your cookies, and a full moon. Reduce it. If it needs prod data, snapshot a fixture.