Welcome to Nox

nox is a command-line tool that automates testing in multiple Python environments, similar to tox. Unlike tox, Nox uses a standard Python file for configuration.

Install nox via pip:

pip install --upgrade nox-automation


These docs are for a pre-release version of Nox, so you’ll need to use pip install --pre nox-automation for now~

Nox is configured via a nox.py file in your project’s directory. Here’s a simple noxfile that runs lint and some tests:

import nox

def tests(session):

def lint(session):
    session.run('flake8', '--import-order-style', 'google')

To run both of these sessions, just run:


For each session, Nox will automatically create virtualenv with the appropriate interpreter, install the specified dependencies, and run the commands in order.

To learn how to install and use Nox, see the Tutorial. For documentation on configuring sessions, see Configuration & API. For documentation on running nox, see Command-line usage.

Projects that use Nox

Nox is lucky to have several wonderful projects that use it and provide feedback and contributions.