anchor.diff:      boot.extraModulePackages =
         optional (elem "nvidia" driverNames) kernelPackages.nvidia_x11 ++ 
         optional (elem "nvidiaLegacy" driverNames) kernelPackages.nvidia_x11_legacy ++
  -      optional (elem "virtualbox" driverNames) kernelPackages.virtualboxGuestAdditions;
  +      optional (elem "virtualbox" driverNames) kernelPackages.virtualboxGuestAdditions ++
  +      optional (elem "ati_unfree" driverNames) kernelPackages.ati_drivers_x11;
   
       environment.etc = optionals cfg.exportConfiguration
         [ { source = "${configFile}";
  
positive.code:             LD_LIBRARY_PATH = "${xorg.libX11}/lib:${xorg.libXext}/lib:${kernelPackages.nvidia_x11}/lib";
            } // optionalAttrs (elem "nvidiaLegacy" driverNames) {
              LD_LIBRARY_PATH = "${xorg.libX11}/lib:${xorg.libXext}/lib:${kernelPackages.nvidia_x11_legacy}/lib";
            } // cfg.displayManager.job.environment;
  
          preStart =
  
negative.code:       ]
        ++ optional (elem "nvidia" driverNames) kernelPackages.nvidia_x11
        ++ optional (elem "nvidiaLegacy" driverNames) kernelPackages.nvidia_x11_legacy
        ++ optional (elem "virtualbox" driverNames) xorg.xrefresh
        ++ optional (elem "ati_unfree" driverNames) kernelPackages.ati_drivers_x11;
        
      environment.systemPackages = config.environment.x11Packages;
      
  