[sodapopcan]

I like this approach. The only problem (or at least one of the problems) is that many people do not have suitable personal projects, as in they might be 10 years old. If one of the goals is to filter out people that don't work on projects in their free time, then this works, but I know many good programmers who don't, or at least they don't anymore due to having kids and other responsibilities outside of work.

As this article touches on, I'm big into pair programming interviews. I was part of the pair programming step at a past company and we'd always use StringCalc [0]. It's starts out super easy and gets gently progressively harder. The goal isn't to finish but to just to see how people think. We would do pretty legit pairing where we'd help if they got stuck on anything or thought we had a better solution. This shows so much about how someone thinks, collaborates, and responds to feedback. Often within 10 mins I could tell how it was going to go. We always had to finish, though, just in case.

Of course it depends on what type of app you have and how your company works and so on and so forth.

[0] https://github.com/MokshankSoni/StringCalc_TDD