Yolk is a Python tool for obtaining information about packages installed by distutils, setuptools and easy_install and querying packages on PyPI (Python Package Index a.k.a. The Cheese Shop).

Yolk can list all the packages installed by distutils or setuptools on your system by >=Python2.5 or packages installed by setuptools if you have <=Python2.4. You can see which packages are active, non-active or in development mode and show you which have newer versions available by querying PyPI.


You can install yolk from pypi (using for instance easy_install yolk) or install from the sources:

$ hg clone
$ cd yolk
$ python install

As of 0.0.7 yolk is in Gentoo's Portage tree as dev-python/yolk and a plugin for Portage named dev-python/yolk-portage:

$ emerge dev-python/yolk


$ yolk -l
List all installed Python packages
$ yolk -a
List only the activated packages installed (Activated packages are normal packages on sys.path you can import)
$ yolk -n
List only the non-activated (--multi-version) packages installed
$ yolk -l -f License,Author nose==1.0
Show the license and author for version 1.0 of the package nose
$ yolk --entry-map nose
Show entry map for the nose package
$ yolk --entry-points nose.plugins
Show all setuptools entry points for nose.plugins

These options query PyPI:

$ yolk -U pkg_name
     Shows if an update for pkg_name is available by querying PyPI

$ yolk -U
     Checks PyPI to see if any installed Python packages have updates available.

$ yolk -F Paste
     Download source tarball for latest version of Paste to your current directory

$ yolk -F Paste -T svn
     Do a subversion checkout for Paste to a directory named Paste_svn in your current directory.

$ yolk -L 2
     Show list of CheeseShop releases in the last two hours

$ yolk -C 2
     Show detailed list of changes in the CheeseShop in the last two hours

$ yolk -M Paste==1.0
     Show all the metadata for Paste version 1.0

$ yolk -M Paste
     Show all the metadata for the latest version of Paste listed on PyPi

$ yolk -D cheesecake
     Show all (source, egg, svn) URL's for the latest version of cheesecake packages

 $ yolk -T source -D cheesecake
     Show only source code releases for cheesecake

 $ yolk -H twisted
     Launches your web browser at Twisted's home page


0.4.1: Fix for -f fields

Add check for integer with -L

0.4.0: Added http proxy support for XML-RPC

Added case-insensitive search for -f

Non-existent packages with -S no longer show entire index (bug was with PyPI)

Fixed exception when package has no metadata

0.3.0: Added -C and -L options for new PyPI XML-RPC methods changelog and updated_releases

Always check package name cache on disk before querying PyPi to see if a package exists and has proper case.

Added -F option to download source, egg or subversion checkouts.

Removed -L RSS feed option because the new updated_releases XML-RPC method is much nicer

Fixed '-D -T egg' so it won't return source if no egg is available

Major refactoring.

Removed dependency on elementtree

0.2.0: Added 'svn' type for -T

A kablillion bug fixes

0.1.0: You can now use -f with -M

More accurate URL's with -D using setuptools

Ability to check for a single package with -U

Uses std Python logging module

Fixed bug so we have correct exit codes

0.0.7: New options: --entry-map and -entry-points

Improved results with --download-links

New plugin system. First plugin available: yolk-portage for Gentoo Linux.

-v option is now --version

-v is now a new option: --verbose

Many bug fixes.

0.0.6: Fix Windows problem which showed all pkgs in develop mode

on some systems.

Fix bad interpreter shebang in example

Start using nose unit tests from

Use restructuredtext in docstrings

0.0.5: Show packages installed in 'development' mode.

Improved output of -l, -n and -a. You can get the previous (<=0.0.4) output by adding '-f Summary'

More sanity checking for various options.

Don't throw exception if there is no package metadata

0.0.4: Added -U option to query PyPI for new versions of packages you have


  • setuptools
  • elementtree (For RSS feed option extra_requires [RSS]) (included in Python >=2.5)