anchor.diff:              default = [];
               description = ''
                 List of additonal arguments to pass to the daemon.
  +            '';
  +          };
  +
  +          configFile = mkOption {
  +            type = nullOr path;
  +            default = null;
  +            description = ''
  +              Kea DHCP6 configuration as a path, see <link xlink:href="https://kea.readthedocs.io/en/kea-${package.version}/arm/dhcp6-srv.html"/>.
  +
  +              Takes preference over <link linkend="opt-services.kea.dhcp6.settings">settings</link>.
  +              Most users should prefer using <link linkend="opt-services.kea.dhcp6.settings">settings</link> instead.
               '';
             };
   
  
positive.code: let
    cfg = config.services.kea;
  
    format = pkgs.formats.json {};
  
    ctrlAgentConfig = format.generate "kea-ctrl-agent.conf" {
      Control-agent = cfg.ctrl-agent.settings;
    };
    dhcp4Config = format.generate "kea-dhcp4.conf" {
      Dhcp4 = cfg.dhcp4.settings;
    };
    dhcp6Config = format.generate "kea-dhcp6.conf" {
      Dhcp6 = cfg.dhcp6.settings;
    };
    dhcpDdnsConfig = format.generate "kea-dhcp-ddns.conf" {
      DhcpDdns = cfg.dhcp-ddns.settings;
    };
  
    package = pkgs.kea;
  in
  
negative.code:             '';
            };
  
            configFile = mkOption {
              type = nullOr path;
              default = null;
              description = ''
                Kea DHCP-DDNS configuration as a path, see <link xlink:href="https://kea.readthedocs.io/en/kea-${package.version}/arm/ddns.html"/>.
  
                Takes preference over <link linkend="opt-services.kea.dhcp-ddns.settings">settings</link>.
                Most users should prefer using <link linkend="opt-services.kea.dhcp-ddns.settings">settings</link> instead.
              '';
            };
  
            settings = mkOption {
              type = format.type;
              default = null;
  