The MediaWiki Developer Summit had three main themes that helped structuring the schedule. These themes were useful, and they can be more useful for the hackathons in Lyon and Mexico City this year, since defining them indvance will help everybody organizing their travel.
Anybody can propose a main theme at https://phabricator.wikimedia.org/T89084
Good candidates include Wikimedia software priorities, project meetings, collaboration with external projects, topics of local relevance... Do not hesitate posting proposals even if they are just an initial idea right now. We want to agree on the main themes by the end of next week in order to help people organizing their travel plans.