public async Task <User> Login(LoginCredentials credentials)
        {
            var account = await AccountCollection.Get(credentials.Username);

            var passwordsMath = WebrewHasher.Instance.VerifyPasswordMatch(credentials.Password, account.Password, SecuritySettings.PasswordHashSecret, account.Salt);

            if (passwordsMath)
            {
                return(await UserCollection.Get(credentials.Username));
            }

            return(await Task.FromResult <User>(null));
        }