I had wanted to add streaming ingestion support to this initially but didn't have time to.  If you can work up a way with the ``Ingester`` protocol to support it (or a new protocol altogether), that would be a good improvement.  Alternatively the protocol for Ingester supports trickling or periodic emission just fine.  Why not batch them into the buffer and emit when that is full and the processing comes to a end?  That may be the easiest compromise.