Moose has no base support for class attributes, and never will, mostly because I think they are a bad idea. That is not to say that I don't like static class data, I think that is fine and can easily be handled by using package level variables and "static" methods. But the idea of inheritable class attributes just make me cringe, but fortunately for those who disagree with me, Dave Rolsky has written MooseX::ClassAttribute which does an excellent job at providing this type of functionality.