Extending User class with additional fields. I don't know if this is the proper way to do it, though?

extensions.dart

import 'package:firedart/auth/user_gateway.dart';

class FBUserData{
  String _fname;
  String _lname;
  String _serialNum;
  String _contactEmail;
  String _verified;
}

extension FBUser on User{
  static FBUserData user = FBUserData();

  String get fname => user._fname;
  String get lname => user._lname;
  String get serialNum => user._serialNum;
  String get contactEmail => user._contactEmail;
  dynamic get verified => getBool(user._verified);

  bool getBool(String value) {
    return (user._verified != null) ? user._verified.toLowerCase() == 'true' : false;
  }

  set fname(String value) {
    user._fname = value;
  }

  set lname(String value) {
    user._lname = value;
  }

  set serialNum(String value) {
    user._serialNum = value;
  }

  set contactEmail(String value) {
    user._contactEmail = value;
  }

  set verified(String value) {
    user._verified = value;
  }
}