Can't use Nvidia offload mode

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11

My good old W530 :smiley:

ok, we are close, I tried to add this on my nvidia.nix:

{ pkgs, ... }:

let
  nvidia-offload = pkgs.writeShellScriptBin "nvidia-offload" ''
    export __NV_PRIME_RENDER_OFFLOAD=1
    export __NV_PRIME_RENDER_OFFLOAD_PROVIDER=NVIDIA-G0
    export __GLX_VENDOR_LIBRARY_NAME=nvidia
    export __VK_LAYER_NV_optimus=NVIDIA_only
    exec "$@"
  '';
in {
  environment.systemPackages = [ nvidia-offload ];

  services.xserver.videoDrivers = [ "nvidia" ];
  hardware.nvidia.package = config.boot.kernelPackages.nvidiaPackages.legacy_470;
  hardware.nvidia.prime = {
    offload.enable = true;

    # Bus ID of the Intel GPU. You can find it using lspci, either under 3D or VGA
    intelBusId = "PCI:0:2:0";

    # Bus ID of the NVIDIA GPU. You can find it using lspci, either under 3D or VGA
    nvidiaBusId = "PCI:1:0:0";
  };
}

But I get this error:

[eyome@nixos:~]$ sudo nixos-rebuild switch
error: undefined variable 'config'

       at /etc/nixos/nvidia.nix:15:29:

           14|   services.xserver.videoDrivers = [ "nvidia" ];
           15|   hardware.nvidia.package = config.boot.kernelPackages.nvidiaPackages.legacy_470;
             |                             ^
           16|   hardware.nvidia.prime = {
(use '--show-trace' to show detailed location information)
building Nix...
error: undefined variable 'config'

       at /etc/nixos/nvidia.nix:15:29:

           14|   services.xserver.videoDrivers = [ "nvidia" ];
           15|   hardware.nvidia.package = config.boot.kernelPackages.nvidiaPackages.legacy_470;
             |                             ^
           16|   hardware.nvidia.prime = {
(use '--show-trace' to show detailed location information)
building the system configuration...
error: undefined variable 'config'

       at /etc/nixos/nvidia.nix:15:29:

           14|   services.xserver.videoDrivers = [ "nvidia" ];
           15|   hardware.nvidia.package = config.boot.kernelPackages.nvidiaPackages.legacy_470;
             |                             ^
           16|   hardware.nvidia.prime = {
(use '--show-trace' to show detailed location information)

Is it a syntaxe error?