anchor.diff:    
         PidFile = ${pidFile}
   
  +      DBHost = ${cfg.dbServer}
  +
         DBName = zabbix
   
         DBUser = zabbix
  +
  +      ${optionalString (cfg.dbPassword != "") ''
  +        DBPassword = ${cfg.dbPassword}
  +      ''}
       '';
   
   in
  
positive.code: with pkgs.lib;
  
  let
  
    stateDir = "/var/run/zabbix";
  
  
negative.code:       '';
      };
  
      services.zabbixServer.dbServer = mkOption {
        default = "localhost";
        description = "Hostname or IP address of the database server.";
      };
  
      services.zabbixServer.dbPassword = mkOption {
        default = "";
        description = "Password used to connect to the database server.";
      };
  
    };
  
    ###### implementation
  
    config = mkIf cfg.enable {
  
      services.postgresql.enable = true;
  
  