Hello, Few years ago I made a branch of buildout: http://svn.zope.org/zc.buildout/branches/sylvain-distribution-cache/ That creates a cache during the installation of the dependencies preventing buildout to recompute this an exponential number of times. The relevant changes can be summarized here (please ignore the Jython changes, I don't know why they were removed): http://svn.zope.org/zc.buildout/branches/sylvain-distribution-cache/src/zc/b... I didn't advertise my changes because of the following facts: - it didn't support multiple working_set using different versions of the same egg, which was possible at the time, - it didn't support multiple versions of Python, which was possible at the time, - it didn't seems to integrate well with the direction that was taking zc.buildout 1.5. I now use zc.buildout 2 and in its README it actually agree with all those facts, so I am basically asking, do you think and/or want me propose a patch to zc.buildout 2 on github, with this global download_cache integrated ? I realize that a global cache sucks, but given the code base, it is difficult not making it global. Regards, Sylvain, -- Sylvain Viollon -- Infrae t +31 10 243 7051 -- http://infrae.com Hoevestraat 10 3033GC Rotterdam -- The Netherlands