What I want to see is at least a few really gnarly bugs that were eventually solved. I want to make sure the tech is backed by people who are 1) highly skilled 2) actually motivated to solve the issues. In short, the kind of people Mickens refers to in his infamous essay ( https://www.usenix.org/system/files/1311_05-08_mickens.pdf ).
I have built this standard up after a few mistakes, where we chose a tool just to realize pretty much everyone working on it was a extremo ultimate rockstar ninja, better known as first-year CS dropout with a god complex.
NB: I'm not saying all first-year dropouts are bad, or that having a degree is in any way mandatory in this field. All I'm saying, is that when our site is down, I'd like to have a few people with 1980s MIT Electrical Engineering degrees on my team. The kind of people who know what a process is, how TCP passes packets, et cetera.