This project utilizes Netlify Functions to handle OAuth login flows, specifically with Intercom as the third-party provider. It creates a custom "login with Intercom" button for an application by using two serverless Lambda functions: `auth.js` and `auth-callback.js`. The `auth.js` function redirects the user to Intercom's login screen after setting up an authorization URI, while the `auth-callback.js` function handles the authorization grant code returned from the successful Intercom login, exchanging it for a valid access token. This flow uses the Authorization Code Grant method and demonstrates how to securely connect with any number of third-party OAuth providers using serverless functions.