How to Integrate Razorpay in a MERN App with Backend Verification

Building a Learning Management System (LMS) like Ascend requires more than just displaying videos; it requires a seamless, secure way for users to purchase content. In this article, I’ll walk you through how I integrated Razorpay into my MERN stack project, ensuring that every transaction is verified on the backend before granting course access. The Workflow Before diving into code, it’s important to understand the handshake between your app and Razorpay. We don't just trust the frontend; we verify every payment signature on our server to prevent fraud. 1. Frontend Setup: Preparing the UI First, we need the Razorpay checkout script in our index.html . This injects the global Razorpay object into our window. <script src= "https://checkout.razorpay.com/v1/checkout.js" ></script> TypeScript Definitions Since I built Ascend with TypeScript, I needed to define the Razorpay types to avoid the dreaded "property does not exist on window" error. I created a src/types/razorpay.d.ts file: export