The kafka sink connector is an open source sink connector that runs on top of Kafka Connect - an open source framework/service that lets you connect external systems (like Batch) with your Kafka instance(s).
The sink connector is available here: github.com/batchcorp/kafka-sink-connector
You can read more about it here.
kafka-sink-connector uses the gRPC API under the hood however it does NOT make use of batching. Due