Immutable. This exact content is served forever at /api/v1/blob/1524faa347a33520.
--- name: refactor description: Restructure existing code without changing its behavior — reduce duplication, improve naming, simplify complex logic, extract helpers, split overgrown functions, untangle dependencies. Use this skill when the user asks to refactor, clean up, simplify, DRY out, rename, extract a helper, split a file, or make code "nicer" — including when they describe code-quality concerns without using the word "refactor" (e.g. "this is messy", "clean it up", "this could be done cleaner"). --- # Refactor Safely restructure code while preserving existing behavior. ## Steps 1. **Verify tests exist** — Before touching anything, confirm test coverage on the code you'll change. If tests are missing, write them first against current behavior. 2. **Name the problem** — What exactly is wrong? - Duplicated logic? Function doing too many things? Poor naming? Tangled dependencies? Wrong abstraction? 3. **Plan the change** — Describe what you'll do before doing it. Small, safe steps. 4. **One change at a time** — Each step keeps the code working. Big rewrites collapse on themselves; small steps stay reversible. 5. **Run tests after each step** — If tests fail, you changed behavior. Undo and try smaller. 6. **Stop when good enough** — Clear, tested, easy to change = done. ## Gotchas - Extract abstractions only when there is real duplication — three similar lines beat a premature helper. - Reach for a design pattern when the problem calls for one, not to demonstrate knowledge. - Confirm with the user before renaming across the entire codebase — the blast radius is bigger than it looks. - Map the downstream callers before touching a public API. - Keep refactors and feature work in separate commits or PRs. - Leave code alone when it works, is clear, and is tested — personal preference is not a reason to refactor.