An option would be to write a super-set of Go with generics that would compile to Go code. what it would do basically is use interface{} everywhere the variable type T is required and insert type assertions for the user. Been thinking about that.

I think that's pretty much how you'd want to do it, it's type erasure just like generics in Java - sure, some people complain about not having reified generics, but I'm more concerned about type-safety, Go already has some runtime reflection capabilities anyway.