You can kind of hack a shared cache using cargo workspaces (put all your rust projects in one directory as part of a workspace) but that is far from ideal. All your projects will share a target directory and Cargo.lock.

I agree though. I don't mind binary sizes in the single megabytes for a release build, and I don't mind clean/rebuild build times that are a few dozen seconds. I do mind the 500MB of build artifacts in a single target directory, multiplied by all the projects I have that share the same version of serde/winapi/syn/quote/insert-common-dependency-here.