I got tired of waiting for lxml to compile over and over again, so I invented a binary packaging format called 'wheel' (of cheese) that uses Metadata 1.2 and .dist-info directories instead of .egg-info, patched pkg_resources.py to be able to load .dist-info directories, implemented "python setup.py bdist_wheel", and patched pip to be able to install .whl files. The gist of the spec is that it is a zip file with the .whl extension containing the contents of 'purelib' for a distribution, plus a Name-1.0.dist-info/ directory with the metadata files, plus Name-1.0.data/subdir directories for scripts, platlib, packaging's "categories", ... My specification so far is at https://docs.google.com/document/d/1mWPyvoeiqCrAy4UPNnvaz7Cgrqm4s_cfaTauAeJW... and an lxml compiled for linux-x86-64 is at https://docs.google.com/open?id=0BxHz5bC4iN5TN0VWTFNrZGtCbWs http://bitbucket.org/dholth/distribute http://github.com/dholth/pip http://pypi.python.org/pypi/wheel Perhaps it will be useful. The implementation is still pretty rough, for example it does not check the architecture while installing, but it could be a handy way to speed up repeated virtualenv builds. Daniel Holth