XProc is a W3C Recommendation to define an XML transformation language to define XML Pipelines. Below is an example abbreviated XProc file: <p:pipeline name="pipeline" xmlns:p="http://www.w3.org/ns/xproc" version="1.0"> <p:input port="schemas" sequence="true"/> <p:xinclude/> <p:validate-with-xml-schema> <p:input port="schema"> <p:pipe step="pipeline" port="schemas"/> </p:input> </p:validate-with-xml-schema></p:pipeline> Here is an equivalent less abbreviated XProc pipeline: