anchor.diff:  
   stdenv.mkDerivation rec {
     pname = "blender";
  -  version = "2.90.1";
  +  version = "2.91.0";
   
     src = fetchurl {
       url = "https://download.blender.org/source/${pname}-${version}.tar.xz";
  -    sha256 = "169xcmm1zkvab14qdxggqc758xdkqs7r7imwi6yx2fl2djacr3g7";
  +    sha256 = "0x396lgmk0dq9115yrc36s8zwxzmjr490sr5n2y6w27y17yllyjm";
     };
   
     patches = lib.optional stdenv.isDarwin ./darwin.patch;
  
positive.code: , colladaSupport ? true, opencollada
  , makeWrapper
  , pugixml, SDL, Cocoa, CoreGraphics, ForceFeedback, OpenAL, OpenGL
  , embree
  }:
  
  with lib;
  
negative.code:       tbb
        makeWrapper
        embree
        gmp
      ]
      ++ (if (!stdenv.isDarwin) then [
        libXi libX11 libXext libXrender
  