RABL (Ruby API Builder Language) is a Rails and Padrino Ruby templating system for generating JSON, XML, MessagePack, and BSON.

It allows one to easily: * create arbitrary nodes named based on combining data in an object * pass arguments to methods and store the result as a child node * render partial templates and inherit to reduce code duplication * rename or alias attributes to change the name from the model * append attributes from a child into a parent node * include nodes only if a certain condition has been met