I like the trend of dependency free libraries in Rust. While cargo makes it easy to add dependencies, it's a double edged sword with extra compile times. I'll keep an eye on this one as a possible replacement for clap which is a bit heavy to compile. Lack of subcommands is a blocker to adoption for me though. The parameter type validation looks interesting. Thanks for sharing!

Hi, I'm the author of climake. Currently starting work on a rewrite of the library that'll introduce subcommands and a revised help system (two main issues of the library currently), https://github.com/rust-cli/climake/issues/6 :)