Zorba is a general-purpose XQuery processor implementing in C++ the W3C family of specifications. It is not an XML database. The query processor has been designed to be embeddable in a variety of environments, such as other programming languages extended with XML processing capabilities, browsers, database servers, XML message dispatchers, or smartphones. Its architecture employes a modular design, which allows customizing the Zorba query processor to the environment’s needs. In particular, the architecture of the query processor allows a pluggable XML store (e.g. main memory, DOM stores, persistent disk-based large stores, and S3 stores).