CUDA not working in distrobox

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1

I can’t figure out how to get CUDA working in distrobox for ai tasks like stable diffusion. I have an NVIDIA 3060 and i’m running nixos unstable.

# Edit tjhis configuration file to define what should be installed on
# your system. Help is available in the configuration.nix(5) man page, on
# https://search.nixos.org/options and in the NixOS manual (`nixos-help`).

{ config, lib, pkgs, ... }:

{
  imports =
    [ # Include the results of the hardware scan.
      ./hardware-configuration.nix
    ];
  nixpkgs.config.allowUnfree = true;
  nixpkgs.config.cudaSupport = true;

  # Use the systemd-boot EFI boot loader.
  boot.loader.systemd-boot.enable = true;
  boot.loader.efi.canTouchEfiVariables = true;

   networking.hostName = "nixos"; # Define your hostname.
networking.interfaces.enp4s0.wakeOnLan.enable = true;
  # Pick only one of the below networking options.
  # networking.wireless.enable = true;  # Enables wireless support via wpa_supplicant.
   networking.networkmanager.enable = true;  # Easiest to use and most distros use this by default.

  # Set your time zone.
   time.timeZone = "Europe/Amsterdam";

  # Configure network proxy if necessary
  # networking.proxy.default = "http://user:password@proxy:port/";
  # networking.proxy.noProxy = "127.0.0.1,localhost,internal.domain";

  # Select internationalisation properties.
   i18n.defaultLocale = "nl_NL.UTF-8";
   console = {
  #   font = "Lat2-Terminus16";
  #   keyMap = "us";
     useXkbConfig = true; # use xkb.options in tty.
   };

  # Enable the X11 windowing system.
  services.xserver.videoDrivers = [ "nvidia" ];  
  hardware.graphics.enable = true;
  hardware.nvidia-container-toolkit.enable = true;
  hardware.nvidia.open = true;
  hardware.nvidia.modesetting.enable = true;
services.xserver.enable = true;


  # Enable the GNOME Desktop Environment.
  services.xserver.displayManager.gdm.enable = true;
  services.xserver.desktopManager.gnome.enable = true;
  

  # Configure keymap in X11
   services.xserver.xkb.layout = "us";
   services.xserver.xkb.options = "eurosign:e,caps:escape";

  # Enable CUPS to print documents.
   services.printing.enable = true;

  # Enable sound.
  # services.pulseaudio.enable = true;
  # OR
   services.pipewire = {
     enable = true;
     pulse.enable = true;
   };

  # Enable touchpad support (enabled default in most desktopManager).
  # services.libinput.enable = true;

  # Define a user account. Don't forget to set a password with ‘passwd’.
   users.users.simon = {
     isNormalUser = true;
     extraGroups = [ "wheel" "docker" "podman"  ]; # Enable ‘sudo’ for the user.
     packages = with pkgs; [
       tree
       spotify  
   ];
   };
#cuda
  environment.variables = {
    CUDA_HOME = pkgs.cudatoolkit;
  };
#Distrobox
virtualisation.podman = {
  enable = true;
 # dockerCompat = true;
};
virtualisation.docker = {
enable = true;
};
   programs.firefox.enable = true;

  # List packages installed in system profile.
  # You can use https://search.nixos.org/ to find more packages (and options).
   environment.systemPackages = with pkgs; [
     vim # Do not forget to add an editor to edit configuration.nix! The Nano editor is also installed by default.
     wget
     google-chrome
     git 
    distrobox       

cudaPackages.cudatoolkit
    nvidia-container-toolkit
    nvidia-docker
    docker    
 ];

  # Some programs need SUID wrappers, can be configured further or are
  # started in user sessions.
  # programs.mtr.enable = true;
  # programs.gnupg.agent = {
  #   enable = true;
  #   enableSSHSupport = true;
  # };

  # List services that you want to enable:

  # Enable the OpenSSH daemon.
  services.openssh.enable = true;

  # Open ports in the firewall.
  # networking.firewall.allowedTCPPorts = [ ... ];
  # networking.firewall.allowedUDPPorts = [ ... ];
  # Or disable the firewall altogether.
  # networking.firewall.enable = false;

  # Copy the NixOS configuration file and link it from the resulting system
  # (/run/current-system/configuration.nix). This is useful in case you
  # accidentally delete configuration.nix.
  # system.copySystemConfiguration = true;

  # This option defines the first version of NixOS you have installed on this particular machine,
  # and is used to maintain compatibility with application data (e.g. databases) created on older NixOS versions.
  #
  # Most users should NEVER change this value after the initial install, for any reason,
  # even if you've upgraded your system to a new NixOS release.
  #
  # This value does NOT affect the Nixpkgs version your packages and OS are pulled from,
  # so changing it will NOT upgrade your system - see https://nixos.org/manual/nixos/stable/#sec-upgrading for how
  # to actually do that.
  #
  # This value being lower than the current NixOS release does NOT mean your system is
  # out of date, out of support, or vulnerable.
  #
  # Do NOT change this value unless you have manually inspected all the changes it would make to your configuration,
  # and migrated your data accordingly.
  #
  # For more information, see `man configuration.nix` or https://nixos.org/manual/nixos/stable/options#opt-system.stateVersion .
  system.stateVersion = "25.05"; # Did you read the comment?

}

When I create an container with the --nvidia flag in distrobox and enter it , it says the nvidia integration is loaded ok, but there’s no cuda suppprt in the container. What’s wrong?