# Disable UEFI.
  boot.loader.systemd-boot.enable = false;

  # Use the GRUB 2 boot loader.
  boot.loader.grub.enable = true;
  boot.loader.grub.efiSupport = false;

  boot.loader.efi.canTouchEfiVariables = false;
  # boot.loader.grub.efiInstallAsRemovable = true;
  # boot.loader.efi.efiSysMountPoint = "/boot/efi";
  # Define on which hard drive you want to install Grub.
  boot.loader.grub.device = "/dev/sda"; # or "nodev" for efi only

{
  inputs.nixpkgs.url = "github:nixos/nixpkgs/nixos-24.11";
  inputs.disko.url = "github:nix-community/disko/latest";
  inputs.disko.inputs.nixpkgs.follows = "nixpkgs";

  outputs = {self, disko, nixpkgs }: {
    nixosConfigurations.koolthing = nixpkgs.legacyPackages.x86_64-linux.nixos [
      ./configuration.nix
      disko.nixosModules.disko
      {
        disko.devices = {
	  disk = {
          main = {
            type = "disk";
            device = "/dev/vdb";
            content = {
              type = "gpt";
              partitions = {
                # Legacy BIOS, MBR-style partition table.
                boot = {
                  size = "1M";
                  type = "EF02"; # Grub MBR.
                };

                # The LUKS-encrypted root.
                luks = {
                  size = "300G";
                  content = {
                    type = "luks";
                    name = "crypted";

                    # Set up with an interactive password and not a keyfile.
                    settings = {
                      allowDiscards = true;
                    };

                    # The Btrfs filesystem.
                    content = {
                      type = "btrfs";
                      extraArgs = ["-f"]; # Overwrite any existing file system.
                      subvolumes = {
                        "/root" = {
                          mountpoint = "/";
                          mountOptions = [
                            "compress=zstd"
                            "noatime"
                          ];
                        };

                        # The home subvolume.
                        "/home" = {
                          mountpoint = "/home";
                          mountOptions = [
                            "compress=zstd"
                            "noatime"
                          ];
                        };

                        # The nix subvolume.
                        "/nix" = {
                          mountpoint = "/nix";
                          mountOptions = [
                            "compress=zstd"
                            "noatime"
                          ];
                        };
                      };
                    };
                  };
                };
              };
            };
          };
	};
        };
      }
    ];
  };
}

Does it make sense to add additional fileSystems attribute for drives I don't want disko to manage/format like:

disko.devices.disk.main = { ... };
fileSystems = { ... };

Will this work correctly?

  grub = {
     efiSupport = true;
     #efiInstallAsRemovable = true; # in case canTouchEfiVariables doesn't work for your system
     device = "nodev";
  };

from here: https://nixos.wiki/wiki/Bootloader

But with disko, i'm getting some error :

       error: The option `virtualisation.vmVariantWithDisko.virtualisation.fileSystems."/etc/secrets".fsType' has conflicting definition values:
       - In `/nix/store/hzaj4d6ari2wq2cbg1j60n9zw42gnshy-source/nixos/modules/virtualisation/qemu-vm.nix': "9p"
       - In `/nix/store/7wf9q0mb1i43x9dr1qlyfaraq15n6sii-source/lib/interactive-vm.nix': "ext4"
       Use `lib.mkForce value` or `lib.mkDefault value` to change the priority on any of these definitions.

I believe this is because the disko vm image actually respects my partitions formats, but that's a bit of a problem for my specific usecase. I can remove the /etc/secrets partition definition in disko, and it works, but do I have any other option ?

I am a little lost trying to get disko working in this setup https://github.com/tcurdt/nixos-hetzner/blob/main/install-nixos.sh

error: attribute 'createScript' missing

       at /nix/store/5dgq6q4jilxz6aipvhr24jsbzhvgy4zx-disko/share/disko/cli.nix:65:7:

           64|     else if (lib.traceValSeq hasDiskoModuleFlake) then
           65|       (builtins.getFlake flake).nixosConfigurations.${flakeAttr}.config.system.build.${diskoAttr}
             |       ^
           66|     else