Using Erlang hot code updates

Hot code update is one of those thing I don't understand, just use a rolling deployment, problem solved. You have a new version of the code without loosing any connection.

It's one of those thing that sound nice on paper but a actually couple your runtime with ci/cd, if you have anything else beside Erlang what do you do? You now need a second solution to deploy code.

The other perspective on this is that, at some level of your system you are always doing a hot code reload: terraform, kubernetes, etc. are taking a new deployment description in and reconciling it with the existing state of the world. Wouldn’t it be nice if this process was just more code in your preferred programming language rather than YAML soup?

BEAM encourages you to structure your program as isolated interacting processes and so it’s not that far from a container runtime in itself.