The most important one to me is not using PHP (THEshittiest programming language ever) and being built upon NodeJS. Also, look at my answer below about the security aspect of it.
Smallish subset here perhaps but then HN is not representative of the wider programming community.
I for one think JavaScript is an utterly hideous language full of all kinds of gotchas and abortions and that the only reason it has any relevance is it got their first.