Don't know if we'll find time to participate, although we do really want to - but if we do, ours will be a scratch-built engine like our other jam games.
Recent community posts
Our game AdvertCity has a detailed procedural city generator on top of a procedural landscape:
Gameplay involves pitting your wits against procedurally generated megacorporations, playing them off against each other by selling them advertising. All megacorporations and city buildings and cybersites have detailed procedurally generated descriptions.
One of our developers talks about the procedural city generation algorithm in this post on a thread in another forum:
Itch.io game page: