Vercel now supports WebSocket connections for Python applications.

WebSockets enable bidirectional communication between client- and server-side code, powering real-time features like interactive AI streaming, real-time chat, and multiplayer live collaboration. Both ASGI and WSGI applications are supported, including frameworks like FastAPI, Django, and Flask.

import fastapi
app = fastapi.FastAPI()
@app.websocket("/api/ws")
async def websocket_endpoint(websocket: fastapi.WebSocket):
    await websocket.accept()
    try:
        while True:
            message = await websocket.receive_text()
            await websocket.send_text(message)
    except fastapi.WebSocketDisconnect:
        pass

Explore the FastAPI AI Chat and Flask AI Chat examples, or read the WebSockets documentation to get started.