Electro.StatePersister.SaveUser C# (CSharp) Method

        public void SaveUser(User user)
        {
            if(usersWriter == null)
            {
                lock(usersFilePath)
                {
                    if(usersWriter == null)
                        usersWriter = new StreamWriter(new FileStream(usersFilePath, FileMode.Append)) {AutoFlush = true};
                }
            }
            usersWriter.WriteLine(user.ToJsonString());
        }

        public User AddUser(string login, string pass, string publicMessage, string privateNotes)
        {
            var user = new User
            {
                Id            = Guid.NewGuid(),
                Login         = login,
                PublicMessage = publicMessage,
                PrivateNotes  = privateNotes,
                PasswordHash  = CryptUtils.CalcHash(pass)
            };

            statePersister.SaveUser(user);
            return(AddUser(user));
        }