Correct; next up, I imagine the compiler and linker working together with annotated code, where you don't deprecate old versions of functions until no more of t

Correct; next up, I imagine the compiler and linker working together with annotated code, where you don't deprecate old versions of functions until no more of the your clients are in that callstack. I believe Erlang has some tricks like this? In my head, I call them Versioned Method Tables. A function signature, and a table of pointers that implement that function, as of different versions of your compiled code...