Skip to main content

Disable virtualenv's download-by-default in tox

Project description

Build Status


Disable virtualenv (>=14)'s downloading behaviour when running through tox.

Wait, why?

A few goals for test suites are repeatability and speed. In modern versions of virtualenv (>=14), virtualenv will reach out to pypi to download the latest version of pip, setuptools, and wheel even when it has a perfectly good copy of the wheeled packages on disk.

A few reasons why downloading is problematic:

  • Reaching out to the network is slow.
  • pypi goes down quite often
  • You may work in a situation where installation should not come from public pypi.
  • If you don't have a network connection, virtualenv will outright fail.
  • Hurts repeatability as you may suddenly get a new version of setuptools / pip
  • setuptools has been unstable in the past, breaking their latest version and compatibility.

How it works

The downloading behaviour of virtualenv can be disabled either by calling virtualenv --no-download or by setting the environment variable VIRTUALENV_NO_DOWNLOAD. This tox plugin sets that environment variable during the virtualenv creation.


$ pip install tox-virtualenv-no-download
# just use tox as you usually would
$ tox ...

Project details

Download files

Download the file for your platform. If you're not sure which to choose, learn more about installing packages.

Source Distribution

tox_virtualenv_no_download-1.1.0.tar.gz (2.3 kB view hashes)

Uploaded source

Built Distribution

Supported by

AWS AWS Cloud computing and Security Sponsor Datadog Datadog Monitoring Fastly Fastly CDN Google Google Download Analytics Microsoft Microsoft PSF Sponsor Pingdom Pingdom Monitoring Sentry Sentry Error logging StatusPage StatusPage Status page