Language 42 offers a very safe and strong metaprogramming system, seamlessly integrated with conventional programming. In this way a simple purely nominal type system with no genericity and polymorphism can support generics, maps and folds. Pushing to the limit this mechanism, we obtain Class Decorators: objects that take a class and "improve itâ by adding useful methods, like equals and toString. Class Decorators can be naturally composed, and the design of a Class Decorators library is currently in progress.