Koop is a Node.js web-server for on-the-fly transformation of geospatial data. The underlying principle of Koop is that your data remains in its native format and location but can be transformed and served to make it consumable by a multitude of clients. Koop makes this work with a plugin architecture built of Providers (plugins that request data from remote sources and transform it to GeoJSON) and Outputs (plugins that transform GeoJSON to other formats for client consumption). The figure below illustrates the flow of data from remote sources through Koop and to clients.