https://www.mediawiki.org/wiki/MediaWiki_Developer_Summit_2015/Lessons_learned
Suggested changes for the next Developer Summit
We should do a three day event instead of a two day event. Two days will be similar to this year, one day will be hacking and networking.
Start using Phabricator earlier in the planning phase
Create templates for etherpads/Phabricator for all sessions
Organize keynotes further in advance
Presenters of smaller sessions should spend less time on introductions and jump into the needed discussions; introductory materials should be posted in advance.
Better food
Encourage people to walk/share taxis