SDE - 1

It was a great experience in 1st round. The interviewer was very humble and polite. He made conversation very comfortable. I was expecting DSA in this round (based on past interview experiences) but we discussed projects. Then the interviewer asked questions based on JS. We started with a basic problem and then dived deeper and deeper in the same. Then the interviewer asked me a question about ReactJS (it was mentioned in my resume) again starting with basics and then level increases. He was more focusing on the optimization of React App (reducing the re-rendering of components). I have to code for a problem on codesandbox.io. He then increased the level by adding more and more constraints.
We had an interview for about 1 hour and 20 min

Interview started with questions on JS and React this time level was too hard. The interviewer was expecting me to write the polyfill for the inbuilt functions like bind, call, apply() and compose(). The interviewer was interested in the internal working of all these functions. I wrote for bind but I didn’t know compose() function in JS then the interviewer explained the function and then asked me to write Polyfill for compose(). He also asked me the oral questions on Virtual DOM, React Lifecycle, Component Re-rendering, Context API, Redux, etc. We also had a conversation on callback function and event loops and their internal working.