ZOO is a WPS (Web Processing Service) open source project released under a MIT/X-11 style license . It provides an OGC WPS compliant developer-friendly framework to create and chain WPS Web services. ZOO is made of three parts:

• ZOO Kernel : A powerful server-side C Kernel which makes it possible to manage and chain Web services coded in different programming languages.
• ZOO Services : A growing suite of example Web services based on various Open Source libraries.
• ZOO API : A server-side JavaScript API able to call and chain the ZOO Services, which makes the development and chaining processes easier.

A brief introduction to WPS and a summary of the Open Source project history with its direct link with FOSS4G will be presented. Then an overview of the ZOO-Project will serve to introduce new functionalities and concepts available in the 1.3.0 release and highlight their interrests for applications developpers. For instance, the caching mechanism and the MapServer WxS automatic publication of result as WMS, WFS or WCS will be presented, this specific enhancement obviously use MapServer to publish and the GDAL library to extract vector or raster metadata informations. Then, examples of concrete services chain use will illustrate the way ZOO-Project can be used to build complete applications in a flexible way by using the service chain concept, creating new service by implementing intelligent chain of service through ZOO-API but also by taking advantage of the publication using OGC standards and caching mechanism to share data between multiple services call. Various use of OSGeo softwares, such as GDAL tools, GEOS, PostGIS, pgRouting, as WPS services by using ZOO-Project will be illustrated by applications presentation. Futur steps and enhancements planned for the ZOO-Project will conclude.