anchor.diff:  { mkDerivation, lib, fetchFromGitHub, cmake, ninja, flex, bison, proj, geos, xlibsWrapper, sqlite, gsl
   , qwt, fcgi, python3Packages, libspatialindex, libspatialite, postgresql
   , txt2tags, openssl, libzip, hdf5, netcdf, exiv2
  -, qtbase, qtwebkit, qtsensors, qca-qt5, qtkeychain, qscintilla, qtserialport, qtxmlpatterns
  +, qtbase, qtsensors, qca-qt5, qtkeychain, qscintilla, qtserialport, qtxmlpatterns
   , withGrass ? true, grass
  +, withWebKit ? true, qtwebkit
   }:
   with lib;
   let
  
positive.code:     [ qscintilla-qt5 gdal jinja2 numpy psycopg2
        chardet dateutil pyyaml pytz requests urllib3 pygments pyqt5 sip owslib six ];
  in mkDerivation rec {
    version = "3.10.11";
    pname = "qgis";
    name = "${pname}-unwrapped-${version}";
  
  
negative.code: 
    cmakeFlags = [ "-DCMAKE_SKIP_BUILD_RPATH=OFF"
                   "-DPYQT5_SIP_DIR=${python3Packages.pyqt5}/share/sip/PyQt5"
                   "-DQSCI_SIP_DIR=${python3Packages.qscintilla-qt5}/share/sip/PyQt5" ]
                   ++ lib.optional (!withWebKit) "-DWITH_QTWEBKIT=OFF"
                   ++ lib.optional withGrass "-DGRASS_PREFIX7=${grass}/${grass.name}";
  
    meta = {
      description = "A Free and Open Source Geographic Information System";
      homepage = "https://www.qgis.org";
      license = lib.licenses.gpl2Plus;
      platforms = with lib.platforms; linux;
      maintainers = with lib.maintainers; [ lsix sikmir ];
    };
  }
  