Many thematic maps and geovisualizations nowadays are being created by designers, journalists, and other non cartographers. Yet, with existing tools it is often difficult to create interactive data visualizations tailored for a particular domain or a specific dataset. We present Unfolding, a library to simplify the creation of interactive maps and geovisualizations. Unfolding provides an API to quickly create and customize visualization applications. In this paper, we introduce the design and functionality of our library. We demonstrate its usability through a collection of examples, and confirm the apparent need of such map library by describing its acceptance in the community.