Nodejs solved all this years ago, now we have super fast shared package managers like pnpm, yarn etc, not to mention deno etc, why can't other languages adopt the same system?
I assume that it is harder for Rust, because it needs to deal with `features`, with cross-compilation, with the developer using `nightly` for some projects, `stable` for others, pinned versions for yet others, etc.
Node supports circular dependencies and arbitrary pre/post-install scripts, which are both disasters for downstream packaging. Node is not a model here.
The CAS that gets symlinked into vendorized directories à la pnpm is the Nix model, which is indeed an improvement that other package managers which support vendorization should incorporate.
That being said, harder doesn't mean unsolvable.