What's that font ?

Berkeley Mono, which I highly recommend if you're into that sort of thing. It's finnicky, has to be hinted right. But the ligatures and stuff are pretty unrivaled IMHO. I think it's like 100 bucks or something, but I bought it once 10 years ago and the license is still good, so it's got an amortization schedule that makes it a perfectly sensible part of a toolbox for a professional if you like myself find it more legible and pleasant than most alternatives.