Simplifying Django dependencies with virtualenv


virtualenv is a tool for simplifying dependency management in Python applications. As the name suggests, virtualenv creates a virtual environment which makes it easy to install Python packages without needing root privileges to do so.

To use the packages installed in a virtual environment you run the activate script in the bin directory of the virtual environment. This is fine when you’re working on the command line, but you don’t want to have to remember this step when running the debug server, and it’s hard to get that to work when the site is deployed under mod_wsgi.

To make things easier you can add the appropriate directory from the virtual environment to Python’s path as part of, or the appropriate fcgi or wsgi control script.

import os
import sys
import siten
root_dir = os.path.abspath(os.path.join(os.path.dirname(__file__), '..'))
site.addsitedir(os.path.join(root_dir, 've/lib/python%i.%i/site-packages'
                % (sys.version_info[0], sys.version_info[1])))

Just add the code above to the top of your file and the ve virtual environment will always be activated when you run the script.

Photo books in a stack (a stack of books) by Evan Bench.


Hi Andrew,

Have you tried Doug Hellmann's virtaulenvwrapper (

Kalle Svensson

24 Aug 2010