I consider clap is a different type of dependency from lalrpop and regex. Clap is part of the application interface and most likely does not change that often.

I consider clap is a different type of dependency from lalrpop and regex. Clap is part of the application interface and most likely does not change that often. Lalrpop and regex are part of the domain logic and probably change fairly often. Today, we can separate a Rust application into "app" and "lib". Most of the change would happen inside lib and app would only need to be compiled for infrequent changes and releases. This allows one to use all the fancy features of clap and mostly ignore the compile time cost. It is annoying to separate a Rust application into "app" and "lib" though, so most people do not do it. They instead opt to replace clap with gumdrop. I think both approaches are valid.