I've enjoyed building things in Nim. I picked it up by building small CLIs, and then eventually by starting a 3D game engine project in Nim. It's the language that I wish would take off already.
I think Nim is great for small CLIs. Some examples are over at: https://github.com/c-blake/bu . To quantify "small", using tools themselves in bu/ (and Zsh *):
I was considering learning Nim. Then I found out about its partial case insensitivity and ignoring of underscores in identifiers. And that was the end of my interest in Nim.