anchor.diff:        '';
       };
   
  +    hardware.nvidia.prime.nvidiaBusId = mkOption {
  +      type = types.str;
  +      default = "";
  +      example = "PCI:1:0:0";
  +      description = ''
  +        Bus ID of the NVIDIA GPU. You can find it using lspci; for example if lspci
  +        shows the NVIDIA GPU at "01:00.0", set this option to "PCI:1:0:0".
  +      '';
  +    };
  +
  +    hardware.nvidia.prime.intelBusId = mkOption {
  +      type = types.str;
  +      default = "";
  +      example = "PCI:0:2:0";
  +      description = ''
  +        Bus ID of the Intel GPU. You can find it using lspci; for example if lspci
  +        shows the Intel GPU at "00:02.0", set this option to "PCI:0:2:0".
  +      '';
  +    };
  +
       hardware.nvidia.prime.sync.enable = mkOption {
         type = types.bool;
         default = false;
  
positive.code: 
        {
          assertion = !syncCfg.enable ||
            (syncCfg.nvidiaBusId != "" && syncCfg.intelBusId != "");
          message = ''
            When NVIDIA Optimus via PRIME is enabled, the GPU bus IDs must configured.
          '';
  
negative.code:   enabled = nvidia_x11 != null;
  
    cfg = config.hardware.nvidia;
    pCfg = cfg.prime;
    syncCfg = pCfg.sync;
  in
  
  {
  