anchor.diff:  , lib
   , stdenv
   , fetchFromGitHub
  -, fetchpatch
   , qmake
   , qttools
   , qttranslations
   , gdal
   , proj
   , qtsvg
  -, qtwebkit
  +, qtwebengine
   , withGeoimage ? true, exiv2
   , withGpsdlib ? (!stdenv.isDarwin), gpsd
   , withLibproxy ? false, libproxy
  
positive.code: 
  mkDerivation rec {
    pname = "merkaartor";
    version = "0.18.4";
  
    src = fetchFromGitHub {
      owner = "openstreetmap";
      repo = "merkaartor";
      rev = version;
      sha256 = "vwO4/a7YF9KbpxcFGTFCdG6SfwEyhISlEtcA+rMebUA=";
    };
  
    patches = [
      # Fix build with Qt 5.15 (missing QPainterPath include)
      (fetchpatch {
        url = "https://github.com/openstreetmap/merkaartor/commit/e72553a7ea2c7ba0634cc3afcd27a9f7cfef089c.patch";
        sha256 = "NAisplnS3xHSlRpX+fH15NpbaD+uM57OCsTYGKlIR7U=";
      })
      # Added a condition to use the new timespec_t on gpsd APIs >= 9
      (fetchpatch {
        url = "https://github.com/openstreetmap/merkaartor/commit/13b358fa7899bb34e277b32a4c0d92833050f2c6.patch";
        sha256 = "129fpjm7illz7ngx3shps5ivrxwf14apw55842xhskwwb0rf5szb";
      })
    ];
  
    nativeBuildInputs = [ qmake qttools ];
  
    buildInputs = [ gdal proj qtsvg qtwebkit ]
      ++ lib.optional withGeoimage exiv2
      ++ lib.optional withGpsdlib gpsd
      ++ lib.optional withLibproxy libproxy
  
negative.code:     lrelease src/src.pro
    '';
  
    qmakeFlags = [
      "TRANSDIR_SYSTEM=${qttranslations}/translations"
      "USEWEBENGINE=1"
    ] ++ lib.optional withGeoimage "GEOIMAGE=1"
      ++ lib.optional withGpsdlib "GPSDLIB=1"
      ++ lib.optional withLibproxy "LIBPROXY=1"
      ++ lib.optional withZbar "ZBAR=1";
  