private function createUser($socialUser)
    {
        $user = [
            'name' => $this->validName($socialUser),
            'email' => $socialUser->email,
        ];
        if ($this->username() === 'username') {
            $user['username'] = $socialUser->nickname;
        }
        $userClass = $this->userModel();
        return $userClass::create($user);
    }