question: Let's say I have 2 separate repos where prefect lives...can I post a 'wait for done" flag type object (similar to airflow) that sends a signal to the 2nd Flow that it can be started?

Hi @Kevin Otte, a couple of things. You can code this with the native requests library like this. You can use

Client.create_flow_run

and lastly you can use the

create_flow_run

built-in task by invoking it with

create_flow_run.run(…)

And regarding your "wait for done aspect", Prefect also has a task allowing you to poll the child flow run for status and block until its (successful) completion called

wait_for_flow_run

. Check out this Discourse topic if you need an example https://discourse.prefect.io/t/how-can-i-create-a-subflow-and-block-until-it-s-completed/94