This is chunked out code that fits into creator-multi. It uses Passport JS to authenticate a user with Google and Twitter via OAuth.
Go to the Google Developers Console and create an OAuth client. They will provide a CLIENT_ID and CLIENT_SECRET that you can add to the .env file. Just cp .env.example .env and update the values.
Go to the Twitter Apps Page and create a new app. They will provide a API_KEY and API_SECRET that you can add to the .env file. Just cp .env.example .env and update the values.
Note: You will need to provide links to your Terms of Use and Privacy Policy pages -- and request access to a user's email -- in order to get their email for storage in the database.