Thanks! This is a nice approach which I will try with our next front-end-candidate.

Currently our process consists of three exercises: A small website-layout where the candidate has to fix two styling-bugs and equalize some container-heights (CSS-Part); a Palindrome-Function (JS-Part); and a discussion where we look at a webpage-layout, and go through how they would structure it HTML/Component-wise and talk about general topics that come up. But I like the colleague-like approach of your way and guess that it'll work better in our case.

Can you name an example of an app which the candidate has to extend?