anchor.diff:        ControlPath ${cfg.controlPath}
         ControlPersist ${cfg.controlPersist}
   
  +      ${cfg.extraConfig}
  +
         ${concatStringsSep "\n\n" (
           map matchBlockStr (
           builtins.attrValues cfg.matchBlocks))}
  
positive.code:         type = types.nullOr types.str;
          default = null;
          description = "The command to use to connect to the server.";
        };
      };
  
  
negative.code:       example = "10m";
        description = ''
          Whether control socket should remain open in the background.
        '';
      };
  
      extraConfig = mkOption {
        type = types.lines;
        default = "";
        description = ''
          Extra configuration.
        '';
      };
  
  