new-api-custom/.agents/skills/vercel-react-best-practices/SKILL.md

name, description

name	description
vercel-react-best-practices	React and Next.js performance optimization guidelines from Vercel Engineering. Use when writing, reviewing, or refactoring React/Next.js code involving components, Next.js pages, Server Components, Server Actions, data fetching, bundle size, rendering behavior, or performance improvements.

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