Bookmap JavaScript API (or JS-API) is a framework for development of Bookmap addons in JavaScript (JS). It supports all the features of Bookmap’s simplified Java API and provides additional helpful functionality. The JS-API has 2 versions: one which includes the API only and the other that includes Stop & Iceberg Tracker engine that allows additional developments based on Bookmap’s Stop & Iceberg Tracker events. You can learn more about the API here