AgentSkillsCN

react-best-practices

Vercel 工程团队提供的 React 与 Next.js 性能优化指南。当您在编写、审查或重构 React/Next.js 代码时，可使用此技能，以确保代码达到最优性能表现。适用于涉及 React 组件、Next.js 页面、数据获取、包体积优化，或性能提升等相关任务。

SKILL.md
--- frontmatter
name: react-best-practices
description: React and Next.js performance optimization guidelines from Vercel Engineering. This skill should be used when writing, reviewing, or refactoring React/Next.js code to ensure optimal performance patterns. Triggers on tasks involving React components, Next.js pages, data fetching, bundle optimization, or performance improvements.

React Best Practices

Overview

Comprehensive performance optimization guide for React and Next.js applications, containing 40+ rules across 8 categories. Rules are prioritized by impact to guide automated refactoring and code generation.

When to Apply

Reference these guidelines when:

  • •Writing new React components or Next.js pages
  • •Implementing data fetching (client or server-side)
  • •Reviewing code for performance issues
  • •Refactoring existing React/Next.js code
  • •Optimizing bundle size or load times

Priority-Ordered Guidelines

Rules are prioritized by impact:

PriorityCategoryImpact
1Eliminating WaterfallsCRITICAL
2Bundle Size OptimizationCRITICAL
3Server-Side PerformanceHIGH
4Client-Side Data FetchingMEDIUM-HIGH
5Re-render OptimizationMEDIUM
6Rendering PerformanceMEDIUM
7JavaScript PerformanceLOW-MEDIUM
8Advanced PatternsLOW

Quick Reference

Critical Patterns (Apply First)

Eliminate Waterfalls:

  • •Defer await until needed (move into branches)
  • •Use Promise.all() for independent async operations
  • •Start promises early, await late
  • •Use better-all for partial dependencies
  • •Use Suspense boundaries to stream content

Reduce Bundle Size:

  • •Avoid barrel file imports (import directly from source)
  • •Use next/dynamic for heavy components
  • •Defer non-critical third-party libraries
  • •Preload based on user intent

High-Impact Server Patterns

  • •Use React.cache() for per-request deduplication
  • •Use LRU cache for cross-request caching
  • •Minimize serialization at RSC boundaries
  • •Parallelize data fetching with component composition

Medium-Impact Client Patterns

  • •Use SWR for automatic request deduplication
  • •Defer state reads to usage point
  • •Use lazy state initialization for expensive values
  • •Use derived state subscriptions
  • •Apply startTransition for non-urgent updates

Rendering Patterns

  • •Animate SVG wrappers, not SVG elements directly
  • •Use content-visibility: auto for long lists
  • •Prevent hydration mismatch with inline scripts
  • •Use explicit conditional rendering (? : not &&)

JavaScript Patterns

  • •Batch DOM CSS changes via classes
  • •Build index maps for repeated lookups
  • •Cache repeated function calls
  • •Use toSorted() instead of sort() for immutability
  • •Early length check for array comparisons