Three rounds of interviews. A phone screen with the recruiter, a technical interview with an engineer, and a third interview with a senior engineer.

The third interview with the senior engineer was very bizarre and left me perplexed after the feedback I received. The role was for a mid-level React position.

The senior engineer began by asking questions about data types. The interviewer dinged me for not mentioning NaN as a data type (it's not, it's a value of the number type, but I did not correct her). She then asked very poorly worded "truthy/falsy" questions that were hard to follow.

We then got into the React portion, which is one of my strengths. She asked questions about React hooks. I named useState() and useEffect(). I proceeded to mention useMemo(), but she stopped me and said that she didn't know what that was and went to the next question.

When talking about hooks, I mentioned how class-based components were still commonly used. She asked for an example, and I brought up an ErrorBoundary, and she did not know what that was.

When I got my chance to ask her questions, I asked about her career path and, in her opinion, at what point she became a senior engineer. She mentioned when she could help juniors install npm packages.

Despite her knowledge gaps, I thought the interview went quite well, and if anything, I was overqualified. I got the rejection from my recruiter a few days later, and the feedback was that my React knowledge was spotty and I am more suited for a junior role.

Name the different data types in JavaScript.

Name some common React hooks.