these 4 derivations will be built:
  /nix/store/h0qv9qkfx6m66ld8miypz15csiq22x3z-Cargo.toml.drv
  /nix/store/03sri018169sp3ijqdvxmkm6aww777sc-source.drv
  /nix/store/ms97jm5yg03kw72bs2y0cazqcdv69hdn-horae-deps-0.1.0.drv
  /nix/store/b03grrqrvjh4cgzpzc314qlindrs5aj1-horae-0.1.0.drv