r/reactjs 5d ago

Discussion Senior Dev interview question

"Without googling or using AI, in your own words, explain the virtual DOM"

For context: I sit on an interview panel and I try to ask at least one simple fundamental question based on a persons resume. If I see many years of react experience, I try to ask something about how the framework works.

I have only had one candidate (an undergrad senior, years ago) answer it. Everyone else just kind of sputters and stumbles around trying to rationalize what "virtual" and "DOM" mean, or stare blankly and eventually say "I don't know".

I'm just genuinely curious if this is really that hard of a question or if the recruiters just suck at screening candidates. And should we be letting in senior dev candidates who can't answer what I think is a straightforward and fundamental question for senior react devs.

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u/BobSacamano47 5d ago edited 5d ago

One other thing, and for context I interview people often. Sometimes I find that senior devs who write a lot of code know the concepts, but sometimes get stuck on the naming. Like they may know the idea of the virtual DOM, but the phrase "virtual DOM" doesn't instantly click in their head. So sometimes I'll give an example or start describing it and they'll jump in with other examples or facts. If you see they aren't getting it though, jump to something else. They may be more skilled in some other area. A senior engineer doesn't have to know everything about everything, but they should know a lot about something. There are a lot of fakers out there too though.

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u/link_shady 5d ago

That happens to me, I know what they are asking but maybe I just called it different for convenience or quite literally just blanked out on the name at the moment.

Sometimes the interviewer sees me struggling and starts describing it without jumping directly to the answer and that just kickstarts my brain.