26. Best Practices and Common Pitfalls

Why Best Practices Matter

React gives you freedom, but that also means it's easy to write messy, hard-to-maintain code. Following best practices ensures your app is clean, scalable, and easy to debug—especially as it grows.

✅ Best Practices to Follow

• Keep components small and focused (Single Responsibility Principle)
• Use clear folder structure for scalability
• Lift state only when necessary
• Use meaningful variable and component names
• Keep UI logic and business logic separated
• Use environment variables for API keys
• Prefer functional components and hooks

❌ Common Pitfalls to Avoid

• Overusing useState instead of combining with reducers or context
• Keeping too much state in the parent component
• Not memoizing expensive calculations or components
• Re-fetching data unnecessarily on every render
• Inline functions or objects causing re-renders
• Deep prop drilling instead of using context or state libraries
• Ignoring error boundaries and crash states

Avoid Re-Renders with memo and useCallback

Unnecessary re-renders slow down your app. Wrap stable components in React.memo and use useCallback to memoize functions passed as props.

const Button = React.memo(({ onClick }) => {
  console.log('Rendered')
  return <button onClick={onClick}>Click</button>
})

export default function App() {
  const handleClick = useCallback(() => console.log('Clicked'), [])
  return <Button onClick={handleClick} />
}

Organizing Your Folder Structure

Instead of dumping everything in a components folder, organize by feature for better scalability.

Mini Project Step

Refactor your app by organizing components into a feature-based folder structure and identify at least two components to memoize for performance improvement.