It's my default for all the reasons you mention.

In fact if I have to ship in a different language, I'll often do a Haskell version first to steer towards isolating IO, enforcing referential transparency, and generally picking up other functional patterns that are a good idea no matter what. Then I'll port the Haskell version to whatever the solution demands.

> do a Haskell version first [...] port

As lower-hanging fruit, to get some style steering, but not the strictness/correctness assist in implementation, there's also doing code sketches in hs - writing without testing - and then asking for whatever code as inspired by / in the spirit of / based on the reference sketch.

With LLMs that’s not a terrible approach. They are generally very good at translating between programming languages.