ImpactFest, Europe's biggest online impact meetup, is organized by the City of the Hague annually. Together with Jaclyn Youngblood from the City of Boston Mayor’s Office of New Urban Mechanics and Mart Duitemeijer from the Netherlands Innovation Network, I explore how using techniques like rapid prototyping, facilitated workshops, and creative thinking exercises helped us co-develop TreeTect, an open-source urban tree-detection algorithm.