I expect it should share a common description, like XmlSchema or IDL and should generate classes for target language. I found Thrift and it's really nice solution, but it doesn't support structures polymorphism. I would like to have collections of base class objects, where I could place instances of subclasses, serialize this and deserialize at the opposite side. Some mechanism of polymorphic behavior support, like Visitor, would be a perfect. Does anybody know something suitable for these requirements?