I do this as well. It's the best signal to noise ratio. Developers spend much more time reading code and understanding the system rather than writing code, ye

I do this as well. It's the best signal to noise ratio. Developers spend much more time reading code and understanding the system rather than writing code, yet interview questions don't acknowledge this. It also works even if the person doesn't know the language because you'll get to see them mapping this new language to something they already know and it can give a good understanding of how well they think of things beyond just the code in front of them.