uvloop

library0.22.1pypypi✓ verified 26d ago

uvloop is a fast, drop-in replacement for Python's built-in asyncio event loop, implemented in Cython and built on top of libuv. The current version is 0.22.1, and it follows a regular release cadence with active maintenance.

http-networking

pip install uvloop

github ↗package ↗

INSTALL

IMPORT

SIG · UVLOOP

uvloop

http-networkingpythonv0.22.1

Install

1.9s avg

Import

202ms

Disk

28MB

Pass rate

10/ 10

Env Coverage10 / 10

glibc

3.9–3.13

musl

3.9–3.13

Install & Compatibility

Where this runs

tested against v0.22.1 · pip install

no network on importno background threads

Install × environment matrix

Each cell = how many times install + import succeeded across repeated harness runs. Partial = flaky.
glibc = Debian/Ubuntu slim · musl = Alpine Linux

musl

py 3.10–3.95 runs

installs and imports cleanly · install 0.0s · import 0.218s · 27.2MB

glibc

py 3.10–3.95 runs

installs and imports cleanly · install 1.9s · import 0.186s · 31MB

28MB installed

● package 28MB

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

uvloop

✓ import uvloop

Ensure that uvloop is installed and imported correctly.

A basic example demonstrating how to use uvloop as the event loop for asyncio applications.

import asyncio import uvloop async def main(): # Your asynchronous code here pass uvloop.run(main())

Debug

Known issues

breakinguvloop does not support Windows at the moment.

fix

Consider using a different event loop implementation on Windows.

affects: all

breakinguvloop may not be compatible with Python versions beyond 3.13.

fix

Verify compatibility with your Python version before using uvloop.

affects: 3.14 and above

gotchauvloop may not handle closed connections gracefully in certain scenarios.

fix

Implement additional error handling to manage closed connections appropriately.

affects: all

Errors

Common errors & fixes

ModuleNotFoundError: No module named 'uvloop'

The `uvloop` package has not been installed in the active Python environment.

fix

pip install uvloop

error: Microsoft Visual C++ 14.0 or greater is required. Get it with 'Microsoft C++ Build Tools': https://visualstudio.microsoft.com/visual-cpp-build-tools/

`uvloop` is a Cython extension that requires a C compiler to build from source, which is often missing on Windows systems by default.

fix

Install the Microsoft C++ Build Tools via the provided link or Visual Studio Installer, then retry `pip install uvloop`.

fatal error: 'uv.h' file not found

When `pip` attempts to build `uvloop` from source (e.g., if a pre-built wheel isn't available), the `libuv` development headers are missing from the system.

fix

Install the `libuv` development package for your operating system (e.g., `sudo apt-get install libuv1-dev` on Debian/Ubuntu, `brew install libuv` on macOS).

Upgrade

Version history

0.22.1latest on PyPI · released Oct 16, 2025

Audit

Dependencies

libuvrequireduvloop is built on top of libuv, a high-performance asynchronous I/O library.

Agent activity

21 hits · last 30 days

node

OpenAI (training)

Resources

githubhttps://github.com/MagicStack/uvloop ↗

packagehttps://pypi.org/project/uvloop/ ↗