{
  lib,
  buildPythonPackage,
  fetchFromGitHub,

  # build-system
  flit-core,

  # dependencies
  filetype,
  defusedxml,

  # optional-dependencies
  pillow-heif,

  # tests
  numpy,
  opencv4,
  pillow,
  pytestCheckHook,
  wand,
}:

buildPythonPackage rec {
  pname = "willow";
  version = "1.8.0";
  format = "pyproject";

  src = fetchFromGitHub {
    owner = "wagtail";
    repo = "Willow";
    rev = "refs/tags/v${version}";
    hash = "sha256-g9/v56mdo0sJe5Pl/to/R/kXayaKK3qaYbnnPXpFjXE=";
  };

  nativeBuildInputs = [ flit-core ];

  propagatedBuildInputs = [
    filetype
    defusedxml
  ];

  passthru.optional-dependencies = {
    heif = [ pillow-heif ];
  };

  nativeCheckInputs = [
    numpy
    opencv4
    pytestCheckHook
    pillow
    wand
  ] ++ passthru.optional-dependencies.heif;

  meta = with lib; {
    description = "A Python image library that sits on top of Pillow, Wand and OpenCV";
    homepage = "https://github.com/torchbox/Willow/";
    license = licenses.bsd2;
    maintainers = with maintainers; [ desiderius ];
  };
}