anchor.diff:  
       globalConfig = mkOption {
         type = promTypes.globalConfig;
  -      default = {};
  +      default = { };
         description = ''
           Parameters that are valid in all  configuration contexts. They
           also serve as defaults for other configuration sections
  
positive.code:     };
    };
  
    promTypes.static_config = types.submodule {
      options = {
        targets = mkOption {
          type = types.listOf types.str;
          description = ''
            The targets specified by the target group.
          '';
        };
        labels = mkOption {
          type = types.attrsOf types.str;
          default = {};
          description = ''
            Labels assigned to all metrics scraped from the targets.
          '';
        };
      };
    };
  
    promTypes.ec2_sd_config = types.submodule {
      options = {
        region = mkOption {
          type = types.str;
          description = ''
            The AWS Region.
          '';
        };
        endpoint = mkOpt types.str ''
          Custom endpoint to be used.
        '';
  
        access_key = mkOpt types.str ''
          The AWS API key id. If blank, the environment variable
          <literal>AWS_ACCESS_KEY_ID</literal> is used.
        '';
  
        secret_key = mkOpt types.str ''
          The AWS API key secret. If blank, the environment variable
           <literal>AWS_SECRET_ACCESS_KEY</literal> is used.
        '';
  
        profile = mkOpt  types.str ''
          Named AWS profile used to connect to the API.
        '';
  
        role_arn = mkOpt types.str ''
          AWS Role ARN, an alternative to using AWS API keys.
        '';
  
        refresh_interval = mkDefOpt types.str "60s" ''
          Refresh interval to re-read the instance list.
        '';
  
        port = mkDefOpt types.int "80" ''
          The port to scrape metrics from. If using the public IP
          address, this must instead be specified in the relabeling
          rule.
        '';
  
        filters = mkOpt (types.listOf promTypes.filter) ''
          Filters can be used optionally to filter the instance list by other criteria.
        '';
      };
    };
  
    promTypes.filter = types.submodule {
      options = {
        name = mkOption {
          type = types.str;
          description = ''
            See <link xlink:href="https://docs.aws.amazon.com/AWSEC2/latest/APIReference/API_DescribeInstances.html">this list</link>
            for the available filters.
          '';
        };
  
        values = mkOption {
          type = types.listOf types.str;
          default = [];
          description = ''
            Value of the filter.
          '';
        };
      };
    };
  
  
negative.code:         relevant Prometheus configuration docs</link> for more detail.
        '';
  
        hetzner_sd_configs = mkOpt (types.listOf promTypes.hetzner_sd_config) ''
          List of Hetzner service discovery configurations.
        '';
  
        http_sd_configs = mkOpt (types.listOf promTypes.http_sd_config) ''
          List of HTTP service discovery configurations.
        '';
  
        # kubernetes_sd_configs
  
        kuma_sd_configs = mkOpt (types.listOf promTypes.kuma_sd_config) ''
          List of Kuma service discovery configurations.
        '';
  
        # lightsail_sd_configs
  
        linode_sd_configs = mkOpt (types.listOf promTypes.linode_sd_config) ''
          List of Linode service discovery configurations.
        '';
  
        marathon_sd_configs = mkOpt (types.listOf promTypes.marathon_sd_config) ''
          List of Marathon service discovery configurations.
        '';
  
        nerve_sd_configs = mkOpt (types.listOf promTypes.nerve_sd_config) ''
          List of AirBnB's Nerve service discovery configurations.
        '';
  
        # openstack_sd_configs
        # scaleway_sd_configs
  
        serverset_sd_configs = mkOpt (types.listOf promTypes.serverset_sd_config) ''
          List of Zookeeper Serverset service discovery configurations.
        '';
  
        # triton_sd_configs
  
        static_configs = mkOpt (types.listOf promTypes.static_config) ''
          List of labeled target groups for this job.
  