I want unified mangling only if it comes with unified basic types. I want a string (maybe not std::string) that I can use not just in C++, but also rust, ada, python, C#, Java, and whatever other language is hot this week that is willing to provide some guarantees (this might include something like deterministic destruction which could toss some of the above out - something to debate). Likewise I want a list type (like std::vector) that I can put in arbitrary types and access by the above languages. The above quickly forces some form a struct type with a layout, and likely also functions (thus class), though we can debate how much we include.