The Leaderboard That Ranked 9 Points Above 100
Why JavaScript's sort() compares numbers as strings, why a 'lazy' comparator works in Safari but breaks in Chrome, and the one-line fix.
5 min read3
CORS Explained Simply — Why Your Fetch Works in Postman but Fails in the Browser
Cross-Origin Resource Sharing in plain language: what blocks your request, what preflight means, and how to fix the errors you'll see in every frontend job.
6 min read1
Debounce vs Throttle — One Sentence to Remember Forever
Two patterns for taming fast events: debounce waits for silence, throttle limits how often. With examples, code, and interview answers.
4 min read
?? vs || — The Default-Value Trap That Breaks Real Apps
`||` treats 0 and '' as missing. `??` only treats null/undefined as missing. Know the difference before it bites you in an interview or in prod.
5 min read1
React useEffect Dependencies — The Bug That Keeps Coming Back
Why your effect reads old state, fires twice, or loops forever — and the simple rules to fix it (interview-ready).
6 min read1