ReactApr 13, 2026
Using index as keysTechnical
Using index as keys
Why using index as key causes subtle bugs, and how to fix it using stable identities.
View article
Hi there,
I write about building things that actually work. Modern web, AI, and the lessons you don’t learn in tutorials.
Join 5+ subscribers.
To receive notifications whenever a new post goes live.
Traffic
69 visits
since last month
Published now
7
articles live on the site
Categories
Software
Architecture
AI
Practices
Personal
College
Featured blogs
Why using index as key causes subtle bugs, and how to fix it using stable identities.
Re-renders are cheap
React avoids expensive DOM operations using diffing and reconciliation—and why most re-renders are not a performance problem.
React re-runs your component, then what?
What happens after a React component re-renders—covering Virtual DOM, diffing, and the 3-phase update process that makes React fast.
React re rendered my component
What triggers React to re render your component, and why re-rendering is not the same as updating the DOM.
React ran my useEffect twice
Why React runs your effects twice in development, what Strict Mode is actually doing behind the scenes, and how it helps you write safer, predictable code.
Discover more
A deep dive into how React tracks hooks internally using an indexed system—and why breaking hook order causes bugs, crashes, and chaos.
React handles state updates internally—why setState is asynchronous, how batching works, and why your state sometimes feels “wrong”.