anchor.diff:  
     meta = with stdenv.lib; {
       description = "A graphics application for digital painters";
  -    homepage = http://mypaint.org/;
  +    homepage = "http://mypaint.org/";
       license = licenses.gpl2Plus;
       platforms = platforms.linux;
       maintainers = with maintainers; [ goibhniu jtojnar ];
  
positive.code:   };
  
    nativeBuildInputs = [
      intltool pkgconfig scons swig wrapGAppsHook
      gobject-introspection # for setup hook
    ];
  
    buildInputs = [
      gtk3 gdk-pixbuf json_c lcms2 libpng librsvg pycairo pygobject3 python
    ];
  
    propagatedBuildInputs = [ numpy ];
  
    postInstall = ''
      sed -i -e 's|/usr/bin/env python2.7|${python}/bin/python|' $out/bin/mypaint
  
negative.code: { stdenv
  , fetchFromGitHub
  , gtk3
  , intltool
  , json_c
  , lcms2
  , libpng
  , librsvg
  , gobject-introspection
  , gdk-pixbuf
  , pkgconfig
  , python2
  , scons
  , swig
  , wrapGAppsHook
  }:
  
  let
    inherit (python2.pkgs) pycairo pygobject3 numpy;
  in stdenv.mkDerivation {
    pname = "mypaint";
    version = "1.2.1";
  