They mostly play nicely together because they operate at different layers. Quinn's flow control handles transport level backpressure (receiver can't consume bytes fast enough), which naturally surfaces to OpenRaft as slower RPC responses. OpenRaft then handles consensus level backpressure by tracking replication progress and adjusting accordingly (e.g., switching to snapshots for lagging peers), it just works. The main benefit is that QUIC's built in flow control means I didn't need manual buffering logic that you'd typically implement over raw TCP.