{
  inputs = {
    nixpkgs.url = "github:nixos/nixpkgs";
    utils.url = "github:numtide/flake-utils";
  };

  outputs = { self, nixpkgs, utils }:
    utils.lib.eachSystem [ "x86_64-linux" ] (system:
      let
        pkgs = import nixpkgs { inherit system; };

        myPkgs = rec { package = pkgs.callPackage ./. { }; };
      in rec {
        packages = utils.lib.flattenTree myPkgs;
        defaultPackage = packages.package;

        devShell = pkgs.mkShell {
          inputsFrom = with packages; [ package ];
        };
      });
}