Caching of various Rust crates/dependencies with different features enabled

[felipesere]

Currently we run cachepot (for legacy reasons) and I am keen to get us back on sccache in the near future.

One thing that is intriguing to me is that we currently have a cache-per-repo strategy. We did this to avoid any issues that would arise from 2 different projects mixing their cached artefacts.
I am wondering, is this concern valid?
I feel like if as a company we had a giant cache, it would be a lot warmer and thus effective. But this only makes sense if compiling the same crate with different features/versions does not lead to issues. For example, different projects use tokio in a couple of versions and with a few different features enabled.

[sylvestre]

I feel that it is quite unlikely that you will have a sha-256 hash collision.