...Or how about doing something as simple as Sign in with Facebook authentication? You can spend hours on it if you are not familiar with how OAuth 2.0 works. When I started this project, my primary focus was on simplicity and ease of use. I also tried to make it as generic and reusable as possible to cover most use cases of hackathon web apps, without being too specific. In the worst case, you can use this as a learning guide for your projects, if for example you are only interested in Sign in with Google authentication and nothing else.