Hm... between two vms, that shouldn't be an issue if networking.hostId is the same for both.

For diskoImagesScript i believe the idea would be that it runs zfs export in the end which also should cause it to import cleanly on another system iiuc.

The PR got merged 🎉 (thanks for your UUID contribution, btw), but I couldn't quite get subvolumes to mount at boot time.

I saw that your PR included code for a custom systemd unit. I haven't tried using that and haven't much experience with writing systemd units, so maybe you could try implementing something with it to get boot-time subvolume mounts to work, if you're interested?

      disko.nixosModules.disko
      {
        disko.devices = {
          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"
                          ];
                        };
                      };
                    };
                  };
                };
              };

# 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"
                          ];
                        };
                      };
                    };
                  };
                };
              };
            };
          };
	};
        };
      }
    ];
  };
}