{
  lib,
  pkgs,
  httpBackend,
  tfPackage,
  tfDirs,
  sources ? import ../../npins,
}:
pkgs.stdenv.mkDerivation {
  name = "tf-repo";
  src =
    with lib.fileset;
    toSource {
      root = ../../.;
      # don't copy ignored files
      fileset = gitTracked ../../.;
    };
  buildInputs = [
    tfPackage
    (pkgs.callPackage ./tf-setup.nix { inherit sources httpBackend; })
  ];
  buildPhase = ''
    runHook preBuild
    for category in ${builtins.toString tfDirs}; do
      pushd "$category"
      source setup
      popd
    done
    runHook postBuild
  '';
  installPhase = ''
    runHook preInstall
    cp -r . $out
    runHook postInstall
  '';
}