I've been writing a smallish multicommand tool (think busybox/git interface) in Rust and using Clap with it's "derive" feature was awesome.

There's learning curve, yes, but I got the interface exactly as I wanted it with very little manual arg processing.

You get autogenerated help, all the --version, etc. stuff. And even shell completion via clap_complete. It's really neat.

Oh and I've tried Anyhow for the first time which is also excellent.

I really like Rust's story for building CLIs.