At most of my corporate clients they have very complex systems with multiple entities to be deployed and tested. (e.g. client software, user database, system, database, identity manager application, etc). They usually don't have an easy way to deploy all this. Neither in production nor for development.
I wonder how open source projects/applications deal with this? Do open source projects tend to be smaller in scope therefore less complex to setup? Do they manage to avoid complexity as no-one pays for their time wasted in setup? I wonder what complex open source projects are there in terms of complexity.
I thought about a couple of examples. Neither of them perfect for my purpose.
Wordpress - The .com site is probably quite complex in terms of deployment but AFAIK the version that can be downloaded from .org is quite simple. It cannot be distributed to multiple servers.
Wikipedia ? Most of the software it is using is open source but it is not itself a downloadable open source project so it does not really fit. Details of their system can be found on Wikipedia
Diaspora - the Facebook replacement is not working yet but it might become such project.
Dreamwidth is originally a LiveJournal fork. Dreamwidth is mostly open source. Its wiki page has information with some production notes. I got some input from them in IRC that I posted on their forum to get further clarifications.
So I am interested in further examples of open source applications/system that are complex in terms of deployment and testing.