Abstract: A computer-implemented method for use with a markup language structured document includes inputting a data template that represents an output data structure and a set of transformation rules corresponding to the nodes in the data template, and generating an output structured document based on the data template and the transformation rules. The method may perform transformation as process that includes compilation and execution. The compilation phase may include compiling transformation rules. The execution phase may comprise traversing the hierarchy in the transformation data template and evaluating each node in the hierarchy based on a corresponding transformation rule in the compiled transformation, the corresponding transformation rule including an instruction for populating the data structure with the source data in the data instance.