"To replace out MediaWiki with a Java-based alternative (XWiki) ended up taking a total fo 24 dev-years over 4+ calendar years for the team, not counting the interruptions to pretty much every other team at Amazon as their pages were getting constantly migrated and un-migrated" I would love to hear more about this. I'm guessing that's a cost of at least $4M? How was this approved? How did they allow it to continue fo…
("how hard can it be" should be on your Words That Prefigure Expensive Disasters list. It's the business equivalent of "hold my beer and watch this")