I think perhaps contrary to popular belief, Mercury choosing Haskell and their early leadership having such a storied experience in it probably played some non-insignificant role in their success.

As a customer of Mercury, it's truly one of the critical companies my toolkit, and I just can't help but feel that their choosing of Haskell made their progress, development and overall journey that much better. I realize that you can make this argument with most languages, and it's not to say that a FP lang like Haskell is a recipe for success, but this intentional decision particularly pre "vibe coding" and the LLM era seems particularly prescient, of course combined with their engineering culture that was detailed in the post.