Eggs, VirtualEnv, and Apt - best practices?

[Scott Sharkey]

Hello all,

Our development group at work seems to be heading towards adopting 
python as one of our standard "systems languages" for internal 
application development (yeah!).  One of the issues that's come up is 
the problem with apt (deb packages) vs eggs, vs virtual environments.
We're probably gonna end up using Pylons or TurboGears for web-based
apps, and I've recommended virtualenv, but one of the other developers 
has had some "inconsistencies" when mixing systems with python installed 
from apt (all our servers are debian or ubuntu based) vs when installed 
under virtualenv.

I have basically recommended that we only install the python base (core 
language) from apt, and that everything else should be installed into 
virtual environments. But I wanted to check to see how other enterprises
are handling this issue?  Are you building python from scratch, or using 
specific sets of .deb packages, or some other process.

Any insight into the best way to have a consistent, repeatable, 
controllable development and production environment would be much 
appreciated.

Suggestions on build/rollout tools (like zc.buildout, Paver, etc) would 
also be appreciated.

Thanks!!!

-Scott