I actually used Functional Jobs to locate a job with an established company that was creating an internal team set to use exclusively a functional language. My

I actually used Functional Jobs to locate a job with an established company that was creating an internal team set to use exclusively a functional language. My experience was not good at all. It turned out that they meant that they had acquired a start-up that made their own proprietary functional language (from scratch, not even building on the parser or lexer or anything from previous languages). The team also said, with a straight face, that they didn't believe in unit testing -- like, they didn't believe that it was even in principle a reasonable thing to do at any time. It really opened my eyes to the fact that when someone claims their team uses "exclusively functional programming" that person actually may not even know what immutability or algebraic data types are. I had always been working on an assumption before that there was a vague correlation between wanting to work with functional techniques and being a quality-minded engineer -- but my experience after getting a job from a place that posted on Functional Jobs totally changed that. I try to be way, way more skeptical now, which is why I am quite skeptical that Jet is using F# more as a hiring trick than as a true engineering ethos.