{
  outputs = { self, nixpkgs }: {
    lib = rec {
      mergeFlakes = flakes: nixpkgs.lib.attrsets.foldAttrs (prev: i: prev // i) {} flakes;
      genSystems = (systems: f:
        (mergeFlakes (map (system:
          builtins.mapAttrs (k: v: { "${system}" = v; }) (f (import nixpkgs { inherit system; }))
        ) systems))
      );
    };
  };
}