Vercel React Best Practices

Use this skill for React and Next.js performance work. The full Vercel guide is stored in references/full-guide.md; do not read the whole file by default.

Workflow

1. Identify the relevant performance area from the task or code under review.
2. Search references/full-guide.md for the matching section or rule heading.
3. Read only the relevant section before changing or reviewing code.
4. Prioritize higher-impact categories before lower-impact micro-optimizations.

Priority Order

1. Eliminating waterfalls: sequential async work, API route chains, missing Promise.all, Suspense boundaries.
2. Bundle size optimization: barrel imports, heavy client modules, dynamic imports, deferred third-party libraries.
3. Server-side performance: Server Actions auth, RSC serialization, per-request deduplication, cross-request caching, after().
4. Client-side data fetching: SWR deduplication, global listeners, passive scroll listeners, localStorage schema.
5. Re-render optimization: derived state, effect dependencies, memo boundaries, functional state updates, transitions, refs.
6. Rendering performance: hydration mismatches, long lists, static JSX, SVG precision, resource hints, script loading.
7. JavaScript performance: repeated lookups, array passes, storage reads, layout thrashing, sort/min-max choices.
8. Advanced patterns: one-time initialization, stable callback refs, effect events.

Reference

• Full compiled guide: references/full-guide.md
• Original project: https://github.com/vercel-labs/agent-skills/tree/main/skills/react-best-practices