gitbutler

Use when creating, changing, running, or debugging shell-based `but` CLI performance scenarios under `crates/but/tests/performance`, including Hyperfine runs, fixture setup, setup-to-test state, and output inspection.

Use when adding or modifying CLI command (`but` commands) under `crates/but/src`.

Use when working on React code in `apps/lite` that derives values during render, adds or consumes a context, subscribes to the redux store or a query, or renders lists of row components — and whenever the lite UI is reported slow, laggy, or re-rendering too much. React Compiler does not prevent these regressions; load this skill BEFORE writing such code, not only when debugging it.

Use when asked to add before/after screenshots of a Lite UI change to a pull request, when a PR touching apps/lite/ui needs its visual change shown, or when extending the screenshot catalogue in apps/lite/e2e/tests/screenshots.spec.ts. Captures both sides locally against seeded fixtures, publishes the surfaces that changed, and posts them to the PR.

Use when adding or modifying tests for one of GitButler's Ratatui TUIs