Synchronizing with consumers in Broadway land

Hi there,
I’m using the magical Broadway to process a set of directories. A single producer fetches the nae of the directories and send them in the pipe for several consumers to process them. Instead of handling the processes myself I subcontract the job to Broadway to handle the boilerplate, back-pressure & shutdown.

But since I don’t spawn the consumers myself I don’t know to capture the end of the job event. When exactly the consumer handles the last directory? How can I wait for that specific moment? Indeed I use Telemetry & catch all the standard events generated by Broadway.

Basically I need to learn how to synchronize with the consumers in Broadway land.