anchor.diff:  
       services.udev.extraRules = nixosRules;
       
  -    services.udev.packages = [extraUdevRules];
  +    services.udev.packages = [ extraUdevRules ];
  +
  +    services.udev.path = [ pkgs.coreutils pkgs.gnused pkgs.gnugrep pkgs.utillinux ];
   
       jobs.udev =
         { startOn = "startup";
  
positive.code:     #udev_log="debug"
    '';
  
  in
  
  {
  
negative.code:       cp -v ${udev}/libexec/rules.d/*.rules $out/
  
        # Set a reasonable $PATH for programs called by udev rules.
        echo 'ENV{PATH}="${udevPath}/bin:${udevPath}/sbin"' > $out/00-path.rules
  
        # Set the firmware search path so that the firmware.sh helper
        # called by 50-firmware.rules works properly.
  