anchor.diff: -{ stdenv, fetchurl, cmake, coin3d, xercesc, ode, eigen, qt4, opencascade, gts
  -, hdf5, vtk, medfile, zlib, python27Packages, swig, gfortran
  -, soqt, libf2c, makeWrapper
  +{ stdenv, fetchurl, cmake, ninja, coin3d, xercesc, ode, eigen, qt5, opencascade-occt, gts
  +, hdf5, vtk, medfile, zlib, python3Packages, swig, gfortran, libXmu
  +, soqt, libf2c, libGLU, makeWrapper, pkgconfig
   , mpi ? null }:
   
   assert mpi != null;
   
   let
  -  pythonPackages = python27Packages;
  +  pythonPackages = python3Packages;
   in stdenv.mkDerivation rec {
     name = "freecad-${version}";
     version = "0.18.2";
  
positive.code:     sha256 = "1r5rhaiq22yhrfpmcmzx6bflqj6q9asbyjyfja4x4rzfy9yh0a4v";
    };
  
    buildInputs = [ cmake coin3d xercesc ode eigen qt4 opencascade gts
      zlib  swig gfortran soqt libf2c makeWrapper  mpi vtk hdf5 medfile
    ] ++ (with pythonPackages; [
      matplotlib pycollada pyside pysideShiboken pysideTools pivy python boost
    ]);
  
    enableParallelBuilding = true;
  
    # This should work on both x86_64, and i686 linux
    preBuild = ''
  
negative.code:   postFixup = ''
      mv $out/share/doc $out
    '';
  
    meta = with stdenv.lib; {
      description = "General purpose Open Source 3D CAD/MCAD/CAx/CAE/PLM modeler";
      homepage = https://www.freecadweb.org/;
  