[frfl]

I kind of worked in a place similar to this. But I think having someone who understands engineering as opposed to just functional programming is important. The codebase I worked on was quite functional, written in TypeScript with libraries like fp-ts, io-ts. It did take a while to figure out some of the things, but ultimately I think the engineer who was leading really understood not to go full pure Haskell-in-JS since others on the team weren't hardcore FP programmers.