So I no longer worry about it.
It's actually about a library, nix, whose mission is "to provide ‘Rust friendly bindings to *nix APIs’".
I thought "A match made in heaven"
But it will probably never happen, because Cargo is too good, haha
The nix package manager has (admittedly, undocumented) support for Rust / Cargo projects.
Because nix and Rust are both great.