setState on Unmounted Component Warning

Fixing the memory leak warning caused by calling setState after a component has been removed.

October 5, 2025

Codemapo

Practical Dev·December 23, 2025

Stop Using useMemo Everywhere: The Cost of Premature Optimization

Obsessively wrapping everything in `useMemo`? It might be hurting your performance. Learn the hidden costs of memoization and when to actually use it.

#React#Performance#Optimization#Hooks

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Why SPA Refresh Returns 404: Understanding Client-Side Routing

Deployed your React app and getting 404 on refresh? Here's why Client-Side Routing breaks on static servers and how to fix it using Nginx, AWS S3, Apache, and Netlify redirects. Includes a debugging guide.

#Web#React#Deployment#Nginx

Why SPA Refresh Returns 404: Understanding Client-Side Routing

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Virtual DOM: The Real Reason React is Fast

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#CS#Web#Frontend#React

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Practical Dev·December 21, 2025

Context API Performance: Why You Should Split Your State

Put everything in one `UserContext`? Bad move. Learn how a single update re-renders the entire app and how to optimize using Context Splitting and Selectors.

#React#Performance#Context API#State Management

Context API Performance: Why You Should Split Your State

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12. One-Line Summary

Async operations continue even after component unmounts, so use useEffect cleanup functions to set cancel flags or use AbortController to cancel requests to prevent memory leak warnings.