anchor.diff:      # open luksRoot and scan for logical volumes
       cryptsetup luksOpen ${device} ${name}
     '';
  +
  +  isPreLVM = f: f.preLVM;
  +  preLVM = filter isPreLVM luks.devices;
  +  postLVM = filter (f: !(isPreLVM f)) luks.devices;
   
   in
   {
  
positive.code: 
          Make sure that initrd has the crypto modules needed for decryption.
        '';
      };
    };
  
  
negative.code:       $out/bin/cryptsetup --version
      '';
  
      boot.initrd.preLVMCommands = concatMapStrings openCommand preLVM;
      boot.initrd.postDeviceCommands = concatMapStrings openCommand postLVM;
    };
  }
  