2026-03-22 –, Yuchengco Hall 4th Flr. Y409 (Workshop Room 2)
Most of today’s popular Python web frameworks like FastAPI, Starlette, and Django Channels are built on a powerful idea called the ASGI protocol. It’s what makes them fast, concurrent, and capable of handling everything from simple HTTP requests to real-time WebSockets.
In this talk, we’ll take a deep dive under the surface to see how ASGI really works, from event loops and async I/O to ASGI scopes, message passing, and lifespan events. We’ll also look at how ASGI connects web servers like Uvicorn with frameworks like FastAPI, forming the bridge that keeps the entire async ecosystem running smoothly.
By the end of the session, you’ll not only understand how ASGI powers modern web frameworks, but also gain the insight that will empower you to debug better, extend confidently, and even build your own.
Over the years, Python’s web ecosystem has evolved from simple, thread-based WSGI apps to powerful, asynchronous frameworks built on top of the ASGI protocol. ASGI changed the game introducing true concurrency, WebSocket support, and the ability to scale Python apps far beyond what WSGI could handle.
In this talk, we’ll take a clear, step-by-step look under the abstractions to see how ASGI actually works. You’ll learn how it acts as the bridge between web servers like Uvicorn or Hypercorn and frameworks such as Starlette and FastAPI.
We will explore:
- How ASGI scopes represent HTTP and WebSocket connections.
- How async message passing with
receiveandsendenables non-blocking communication. - How frameworks like Starlette build on ASGI to implement routing, middleware, and lifespan events.
- And how ASGI’s design makes modern frameworks scalable, flexible, and ready for real-time workloads.
A seasoned software engineer with over 10 years of experience designing and delivering high-performance, scalable software systems. Currently works as a Senior Lead Engineer at bKash Limited, focusing on building reliable backend platforms at scale.