Currently there are a bunch of really wacky hacks required to get
nixpkgs path correctly set up under flake configs such that `nix run
nixpkgs#hello` and `nix run -f '<nixpkgs>' hello` hit the nixpkgs that
the system was built with. In particular you have to use specialArgs or
an anonymous module, and everyone has to include this hack in their own
configs.
We can do this for users automatically.
NixOS/nixpkgs@e456032add
Co-authored-by: Antoine Cotten <hello@acotten.com>
