For what is worth, you can use https://lib.rs to see the earliest version a crate supports. For Rust 1.63.0, you will have to rely on Clap 4.0.32 from December 2022, instead of anything newer (which only support 1.64.0+): https://lib.rs/crates/clap/versions
For anstream, the situation seems more difficult for you, as it doesn't seem that there's any (non-yanked?) release that supports <1.64.0: https://lib.rs/crates/anstream/versions
Thanks! I was looking for a page like that on docs.rs, crates.io, and possibly on lib.rs as well, but missed it; that is likely to be useful in the future. Actually now I see it on crates.io as well, <https://crates.io/crates/anstream/versions>. Or maybe I saw it before, and just have not found versions <= 1.63.
