The tricky part is transferring state between hot reloads, and that's part of what Erlang was designed around. State has to be passed in and owned by the callee

The tricky part is transferring state between hot reloads, and that's part of what Erlang was designed around. State has to be passed in and owned by the callee. And if the format that state is stored in changes, you need to handle that translation in the new version. It's definitely doable in C and C++. The question is whether it is easier to re-implement a bunch of what Erlang does for you, or to just use something that supports it directly. Good ol' "build or buy?"