Call callback-function inside Behaviour-Module

I would give you a thumbs up during code review on a PR like this – it’s all good.

If you are worried about this approach then the only other practice that’s more “micro” would be to only pass function references – but then you would be losing the compiler warnings if a contract is violated i.e. if the function has the same arity but accepts different kinds of arguments.

So IMO callback modules are the right solution here.