{
  perSystem =
    {
      pkgs,
      lib,
      ...
    }:
    let
      packages = lib.packagesFromDirectoryRecursive {
        inherit (pkgs) callPackage;
        directory = ./packages;
      };
    in
    {
      legacyPackages = packages;
      packages = lib.filterAttrs (
        _: pkg:
        let
          isDerivation = lib.isDerivation pkg;
          availableOnHost = lib.meta.availableOn pkgs.stdenv.hostPlatform pkg;
          isBroken = pkg.meta.broken or false;
        in
        isDerivation && !isBroken && availableOnHost
      ) packages;
    };
}