We're active users of PureScript at Lumi (W15). We started experimenting with Haskell on the backend about two years ago and it was a huge success for many of the same reasons stated by the OP. We've now completely moved from Node to Haskell for our API. Since then we've continued to double down on type-driven development and bringing it to the frontend with PureScript made sense. It helps that Phil Freeman, its creator, is on our team :)

We've been dipping our toes into open-sourcing more PureScript libraries, such as our React bindings: https://github.com/lumihq

Can't speak for HN, but I really liked tinkering with it. If I remember correctly, its data structures were just basic JS data structures under the hood (e.g. JS arrays, objects, etc), which meant it didn't show the same perf benefits of a language that uses persistent data structures under the hood (e.g. Clojure, OCaml/Reason). I wonder if that has changed since I took a look.

Cool you liked it - I recently had a similar experience replacing from JQuery froms with it.

It does by default it provide access to native JS data structures, but you don't have to use them e.g. there are persistent structures as well. https://pursuit.purescript.org/packages/purescript-ordered-c... though I don't quite understand the comment that persistent data structures are "slower" than native structures; I thought usually, it's the other way around.