Wikimedia Bugzilla is closed!

When I first wrote the multiwiki functionality during the Zürich hackathon, I made a fundamental assumption that the primary reason for wanting to run multiple wikis in a single VM would be to configure radically different collections of extensions and configuration on each wiki. As usage of the multiwiki core has expanded it has become apparent that this is a fundamentally flawed assumption. It seems to be much more likely that secondary wikis are wanted to to add functionality to the wiki farm as a whole (central auth database, wikidata storage, common image storage) with the same extensions available across the farm. An as yet unimplemented, but desirable, use case is wikis for alternate default language.

The initialization provided by the multiversion system should be changed to load the extensions and configuration of the primary wiki (as provided by roles) as a baseline that a particular multiwiki instance can build upon as desired. By shifting the model of a multiwiki to reconfigure and augment the features of the base wiki, it will be easier to disentangle the features of a given extension from the role for a given multiwiki instance.