I wish Standard ML had a strong ecosystem and things like a good dependency manager/package manager. I really liked it. But there is even less of an ecosystem around it than some other niche languages, and I've gone into the rabbit hole of writing everything myself too often, to know that at some point I will either hit the limit of my energy burning out, or the limits of my mathematical understanding to implement something. For example how to make a normal distribution from only having uniform distribution in the standard library. So many approaches to have an approximation, but to really understand them, you need to understand a lot of math.

Anyway, I like the language. Felt great writing a few Advent of Code puzzles in SMLNJ.