simstudioai--sim/.cursor/commands/you-might-not-need-a-memo.md

You Might Not Need a Memo

Arguments:

• scope: what to analyze (default: your current changes). Examples: "diff to main", "PR #123", "src/components/", "whole codebase"
• fix: whether to apply fixes (default: true). Set to false to only propose changes.

User arguments: $ARGUMENTS

References

Read before analyzing:

1. https://overreacted.io/before-you-memo/ — two techniques to avoid memo entirely

Anti-patterns to detect

1. State can be moved down instead of memoizing: Move state into a smaller child so the slow component stops re-rendering without memo.
2. Children can be lifted up: Extract stateful part, pass expensive subtree as children — children as props don't re-render when parent state changes.
3. useMemo on cheap computations: Small array filters, string concat, arithmetic don't need memoization.
4. useMemo with constantly-changing deps: Deps change every render = useMemo does nothing.
5. useMemo to stabilize props for non-memoized children: If the child isn't wrapped in React.memo, stable references don't matter.
6. React.memo on components that always receive new props: Fix the parent instead.
7. useMemo for derived state: Just compute inline during render.

Steps

1. Read the reference above
2. Analyze the specified scope for the anti-patterns listed above
3. If fix=true, apply the fixes. If fix=false, propose the fixes without applying.