{
  stdenv,
  python3Packages,
  coreutils,
  zopfli,
  brotli,
  findutils,
  dart-sass,
}:
stdenv.mkDerivation {
  name = "e11sync-static";
  src = ../app;
  nativeBuildInputs = [
    python3Packages.django
    python3Packages.django-compressor
    dart-sass
  ];
  patchPhase = ''patchShebangs --build manage.py'';
  buildPhase = ''
    mkdir -p static
    export E11SYNC_STATIC_ROOT=static
    export E11SYNC_DEBUG=
    export E11SYNC_COMPRESS_OFFLINE=1
    ./manage.py collectstatic
    ./manage.py compress

    ${findutils}/bin/find static/CACHE -name '*.css' | \
      ${findutils}/bin/xargs -P''$(${coreutils}/bin/nproc) -I{} sh -c \
        "${zopfli}/bin/zopfli {} && ${brotli}/bin/brotli {}"
  '';
  installPhase = ''mv static $out'';
}