Ask HN: What do you use to make CLIs?

I am curious what people reach for when writing CLIs these days; specifically what language, libraries (if any), and why?

By CLI, I mean any executable program or script like git that supports commands, sub-commands, and POSIX-style flags.

I mostly work in Go, and have been happy with the standard library[1] or Cobra[2]. I also write a lot of shell scripts.

I thought it would be interesting to see some other approaches.

[1]: https://pkg.go.dev/flag [2]: https://cobra.dev