{
  pkgs,
  qemu_list,
  vbox_list,
  hyperv_list,
  ...
}:

let

  general = {
    stage = "build";
    cache = [
      {
        key = {
          files = [ "sources/build.pkr.hcl" ];
        };
        paths = [ "./packer_config/" ];
      }
    ];
    rules = [
      {
        "if" = "$CI_COMMIT_TAG";
        variables = {
          EXCEPT = "";
          JOB_PREFIX = "upload";
        };
      }
      {
        "if" = "$CI_COMMIT_TAG =~ \"/^$/\"";
        variables = {
          EXCEPT = "-except=upload";
          JOB_PREFIX = "ci";
        };
      }
    ];
    needs = [
      {
        pipeline = "$PARENT_PIPELINE_ID";
        job = "generate";
        artifacts = true;
      }
    ];
    script = [
      "nix run \".#\\\"\${JOB_PREFIX}\${buildcmd}\\\"\" || exit 1"
    ];
  };

  variables = {
    PACKER_CONFIG_DIR = "./packer_config/";
    PACKER_CACHE_DIR = "./cache/";
    PACKER_LOG = "1";
  };

  continue = {
    stages = [
      "build"
      "release"
    ];
    "qemu.amd64" = general // {
      variables = variables // {
        only = "-only=qemu.amd64";
      };
      tags = [ "qemu" ];
      parallel = {
        matrix = qemu_list;
      };
      before_script = [
        "echo $BUILD"
        "env"
      ];
    };
    "virtualbox-iso.amd64" = general // {
      variables = variables // {
        only = "-only=\"virtualbox-iso.amd64\"";
      };
      tags = [ "vbox" ];
      parallel = {
        matrix = vbox_list;
      };
    };
    "hyperv-iso.amd64" = general // {
      variables = variables // {
        only = "-only=\"hyperv-iso.amd64\"";
      };
      tags = [ "hyperv" ];
      parallel = {
        matrix = hyperv_list;
      };
      script = [
        "packer init sources"
        "packer build -only=\"hyperv-iso.amd64\" -var-file=\"\${distro}\" -var build=\${BUILD} -var cpus=2 -var memory=4096 \${EXCEPT} sources"
        "if (-not $?) { throw \"Error in build\" }"
      ];
    };
    "Create release" = {
      stage = "release";
      image = "registry.gitlab.com/gitlab-org/release-cli:latest";
      rules = [
        {
          if = "$CI_COMMIT_TAG";
        }
      ]; 
      script = "echo \"Tagging as released\"";
      needs = [
        {
          pipeline = "$PARENT_PIPELINE_ID";
          job = "continue";
          artifacts = true;
        }
        {
          pipeline = "$PARENT_PIPELINE_ID";
          job = "generate";
          artifacts = true;
        }
      ];
      release = {
        tag_name = "$CI_COMMIT_TAG";
        description = ''
          Release $CI_COMMIT_TAG, found on [Vagrant Cloud](https://app.vagrantup.com/boxen/)
          as version v''${BUILD}
        '';
      };
    };
  };
in
pkgs.writeText "continue.yml" (builtins.toJSON continue)