Overview

Uvicorn 0.42, released on March 16, 2026, optimizes request body processing.

Main Features

Optimized request body

HTTP request body parsing has been optimized, reducing memory consumption and improving throughput for large requests.

python 
import uvicorn

async def app(scope, receive, send):
    if scope['type'] == 'http':
        body = b''
        while True:
            msg = await receive()
            body += msg.get('body', b'')
            if not msg.get('more_body'):
                break
        # Optimized body processing

uvicorn.run(app, host='0.0.0.0', port=8000)

Performance improvements

Benchmarks show a 15% latency reduction for POST requests with large bodies.

Sources