anchor.diff:          {
             foo = {
               server = "192.0.2.1";
  -            extraConfig = "-p mysecurepassword";
  +            extraConfig = "-v";
             }
           }
           '';
  
positive.code:           type = types.str;
            default = "";
            description = "Additional command line parameters";
            example = "-p mysecurepassword";
          };
        };
  
  
negative.code:         description = "hans client - ${name}";
          after = [ "network.target" ];
          wantedBy = [ "multi-user.target" ];
          preStart = ''
            cat > /run/hans/${name}-script << EOF
              #!/bin/sh
              ${pkgs.hans}/bin/hans -f -u ${hansUser} ${cfg.extraConfig} -c ${cfg.server} ${optionalString (cfg.passwordFile != "") "-p $(cat \"${cfg.passwordFile}\")"} 
            EOF
            chmod 700 /run/hans/${name}-script
          '';
          script = "/run/hans/${name}-script";
          serviceConfig = {
            RestartSec = "30s";
            Restart = "always";
            RuntimeDirectory = [ "hans" ];
          };
        };
      in
  