This section describes how to extend the capability of Saxon XSLT stylesheets and XQuery queries by adding extension functions, extending the configuration and other user hooks.
The most important extensibility mechanism is the ability to write extension functions in Java or C# that can be invoked from XPath expressions (either free-standing XPath expressions, or expressions embedded in XSLT, XQuery, or XSD).
For general information about extension functions, see Extension functions.
To write extension functions in Java, see Extension functions (Java).
To write extension functions in C#, see Extension functions (C#).
For other extensibility mechanisms, see the following sections: