# React Best Practices
## Project Structure
```
src/
├── assets/ # Static files
├── components/ # Shared components
│ ├── ui/ # Basic UI components
│ └── common/ # Common components
├── features/ # Feature modules
│ └── users/
│ ├── api/ # API calls
│ ├── hooks/ # Custom hooks
│ └── types/ # TypeScript types
├── hooks/ # Shared hooks
├── services/ # API services
├── store/ # State management
├── types/ # Shared types
└── utils/ # Utilities
```
## Component Patterns
- Use functional components
- Keep components small
- Extract reusable logic to hooks
- Implement error boundaries
- Use React.memo wisely
## State Management
- Local state for UI
- Context for themes/auth
- Redux for complex state
- Use proper selectors
- Normalize data
## Performance
- Lazy load routes
- Use React.Suspense
- Implement code splitting
- Optimize re-renders
- Cache API responses
## Data Fetching
- Use React Query/SWR
- Handle loading states
- Implement error handling
- Cache responses
- Optimize requests
## Forms
- Use form libraries
- Validate inputs
- Handle submissions
- Show feedback
- Maintain accessibility
## Testing
- Test user interactions
- Mock API calls
- Test error states
- Use testing library
- Write integration tests
## Security
- Sanitize inputs
- Prevent XSS
- Use HTTPS
- Handle auth properly
- Validate data
## TypeScript
- Define proper types
- Use interfaces
- Type props strictly
- Handle null checks
- Use generics wisely
## Development
- Use ESLint
- Format with Prettier
- Write documentation
- Review code
- Use CI/CD