Yep, I think there should be some included Config behaviour module which handles the serialising / deserialising of a config file, and genservers can register themselves against it, and when the config changes the registered genservers get terminated and restarted gracefully.

I don't think it's very much work - but everytime i try to build something like this I go down this path of trying to work out exactly what the architecture should be like.

Maybe it's a config application you include in extra_applications. How would you tell it the format of the file? How could you do validations?

And then maybe do an escript or similar for configuring it on the fly - something like "elixir_set <variable> <value>"