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+# Contributing to TwinTrack
+
+1. Every change starts as an issue. Pick or create one before you start.
+2. Branch from `main` as `issue-<number>-<short-name>`.
+3. Open a pull request with `Closes #<number>` in the description.
+4. The other team member reviews it, leaves at least one comment or question,
+   and approves once it is addressed. You cannot approve your own pull request.
+5. After approval, merge. The issue closes automatically.
+6. `main` is protected: no direct pushes.
+7. Never commit passwords, tokens, private keys or personal data.