I haven't used Nim in prod, but I messed around with it quite a bit a few years ago and it really hits a sweet spot in terms of language size (features, not ecosystem) and expressiveness. At its best, it really does feel like a tidier version of Python with static types.

A small thing in Nim that I regularly miss in Python: `discard` is incredibly useful while reading code and telegraphs the writer's intentions to the reader much more clearly. Oh, and the simple null-coalescing operator. I haven't written enough to see the macro system or FFI used to their fullest, but both features seem well designed. Definitely one of the more interesting recent languages in my opinion.