Evaluator-Orchestrator callbacks is the ability for code implementations, which are executed by the Evaluator, to make function calls back to the Orchestrator as part of their execution. Previously, we've use the words "reentrant" and "reentrancy" to describe this ability (and they still may appear in some places), but we've decided not to use those words anymore.
This is an umbrella ticket to collect all tasks related to this capability.

