RABL
General ruby templating with json, bson, xml, plist, msgpack support
RABL, or Ruby API Builder Language, is a Ruby templating system for constructing structured API responses from application objects. It separates the underlying data model from the representation returned to API consumers. Templates use a Ruby DSL to select attributes, define custom nodes, nest child objects, and transform collections. Output formats include JSON, XML, MessagePack, BSON, and property lists.