This blog was originally published on Descope . Looking to implement authentication middleware in your app? Most modern frameworks support middleware functions that let you intercept user requests, verify tokens, and control access—all in a centralized way. In this blog, we'll walk through how authentication middleware works and how to implement it effectively using code examples in Node.js and Python. Once you understand the basics, we'll show how Descope's tools can streamline the process with out-of-the-box support for token validation, role checks, and more. What is authentication middleware in web apps In the context of web development, authentication middleware is a function that intercepts incoming requests and runs logic before or after those requests reach your application's core handlers. Middleware gives you a centralized way to manage access control, freeing up developer time to focus on business logic instead of duplicating auth checks across routes.…