{ description = "Flake utils demo"; inputs.flake-utils.url = "github:numtide/flake-utils"; outputs = { self, nixpkgs, flake-utils }: flake-utils.lib.eachDefaultSystem (system: let pkgs = nixpkgs.legacyPackages.${system}; in rec { packages.hello = pkgs.hello; defaultPackage = packages.hello; apps.hello = flake-utils.lib.mkApp { drv = packages.hello; }; defaultApp = apps.hello; } ); }