{
  description = "what does the cow say";

  inputs = {
    nixpkgs.url = "github:NixOS/nixpkgs";
  };

  outputs = { self, nixpkgs }: {

    devShells = {
      x86_64-linux.default =
        let
          pkgs = import nixpkgs { system = "x86_64-linux"; };
        in
          pkgs.mkShell {
            packages = [ pkgs.cowsay ];
          };
    }; # devShells

  }; # outputs
}