I'd say the more problematic part of hiring is in the interview stage, where inevitably you'll be asked questions around binary search trees, merge sorts, and the like. (Admittedly, I am also guilty of using such interview questions myself in the past as an interviewer.) I find that it's actually more reasonable to expect knowledge and working experience with all the tech tools you listed, than actually asking about inverting a binary search tree. I don't have good answers for what one should ask instead.