It would be good to write up a postmortem of the problems that happened with the recent A/B test on the Wikipedia portal, so that:

1. we have a clear, overall description of the problems in a single public place we can point to (e.g. for the quarterly review)
2. we're clear on exactly what caused the problem
3. we have documented steps to prevent the same problem from occurring again

Much of this is actually already done, but it's in varying different places, so part of this task will simply involve pulling in that text.

Examples of similar incident documentation are here: https://wikitech.wikimedia.org/wiki/Incident_documentation

I don't know whether to suggest that this goes on wikitech or on mediawiki. Wikitech fits better, but mediawiki is where most of our stuff is. Fortunately, it's super easy to move if someone complains, so let's just go with putting it on mediawiki.org.