partial.nix

{
      nixosConfigurations = pkgs.nixosConfigurations // {
        # attrs of interest:
        # * config.system.build.zfsImage
        # * config.system.build.uploadAmi
        zfs-ami = import "${nixpkgs}/nixos" {
          configuration = { pkgs, lib, ... }:
          {
            imports = [
              ops-lib.nixosModules.make-zfs-image
              ops-lib.nixosModules.zfs-runtime
              "${nixpkgs}/nixos/modules/profiles/headless.nix"
              "${nixpkgs}/nixos/modules/virtualisation/ec2-data.nix"
            ];
            nix.package = self.packages.x86_64-linux.nixFlakes;
            nix.extraOptions = ''
              experimental-features = nix-command flakes
            '';
            systemd.services.amazon-shell-init.path = [ pkgs.sops ];
            nixpkgs.config.allowUnfreePredicate = x: builtins.elem (lib.getName x) [
              "ec2-ami-tools"
              "ec2-api-tools"
            ];
            zfs.regions = [
              "eu-west-1"
              "ap-northeast-1"
              "ap-northeast-2"
              "eu-central-1"
              "us-east-2"
            ];
          };
          system = "x86_64-linux";
        };

}