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Comprehensive performance optimization guide for React and Next.js applications, maintained by Vercel. Contains 64 rules across 8 categories, prioritized by impact to guide automated refactoring and code generation.

Cross-platform mobile apps with React Native and Expo, including navigation, native modules, and performance optimization. \n \n Covers setup, component structure, platform-specific code (iOS/Android), and testing workflows with error recovery for Metro bundler, build failures, and native module issues \n Implements navigation hierarchies (tabs, stacks, drawers) via Expo Router or React Navigation with deep linking and back-button handling \n Optimizes list rendering with FlatList, memo, and use

Write and review React Native component tests using Testing Library v13 and v14. \n \n Covers render patterns, screen queries (getBy/getAllBy/queryBy/findBy variants), Jest matchers, userEvent interactions, fireEvent, and async patterns with version-specific behavior \n Automatically detects your project's RNTL version (v13 for React 18, v14 for React 19+) and applies correct API signatures and sync/async rules \n Provides query priority guidance (getByRole first), interaction best practices (us

Memoization, code splitting, and virtualization patterns for optimizing React application performance. \n \n Covers four core optimization techniques: memoization (React.memo, useMemo, useCallback), code splitting with lazy/Suspense, virtualization for large lists, and state management strategies to minimize render cascades \n Includes React 18+ concurrent features (useTransition, useDeferredValue) for improved responsiveness and perceived performance \n Provides profiling workflow using React D

React patterns for hooks, effects, refs, and component design with escape hatch guidance. \n \n Effects synchronize with external systems only (WebSocket, third-party libraries, browser APIs); most component logic should avoid Effects entirely \n Common anti-patterns: derived state, expensive calculations, prop-change resets, and event handling all belong outside Effects—use render calculations, useMemo, key props, and event handlers instead \n Effect dependencies must never be suppressed; use u

Complete development guidelines for building maintainable, scalable applications with Next.js, React, Redux Toolkit, and TypeScript.

Performance and architecture patterns for React Native + Expo apps. Rules ranked by impact — fix CRITICAL before touching MEDIUM.

23 performance optimization rules for React and Vite across build, code splitting, development, assets, environment, and bundle analysis. \n \n Covers six rule categories prioritized by impact: build optimization and code splitting (critical), development and asset handling (high), environment config and bundle analysis (medium) \n Includes route-based lazy loading with React.lazy() and Suspense, manual vendor chunk separation, and strategic prefetching patterns \n Provides recommended vite.conf

Build scalable, maintainable React components using modern patterns including functional components, hooks, composition, and TypeScript for type safety.

Comprehensive performance optimization guide for React and Next.js applications, maintained by Vercel. Contains 45 rules across 8 categories, prioritized by impact to guide automated refactoring and code generation.