Hi @sosborn-trumid,
Can I ask for the use case. In Akka Streams Source converts the data into streams, flow transforms that data and allows you to materialize it and Sink is the consumer of that data. If you want to lets say send data from a source to an Actor. You can use Tell (!) pattern to achieve it as Sink is consuming it.
In Sink you can apply foreach and send each data unit as a message.
[Sink.foreach[Int]( x => Actor ! newNumber(x))
If you want to ensure that the data is sent to the Sink only when its available - check out Conflate in Flow that acts like fold operator but emits the result only when downstream is ready.