Check out the docs at Apache Kafka web site: http://kafka.apache.org/documentation/streams/
Find more links about Kafka Streams at Kafka Ecosystem page.
KIP-313: Add KStream.flatTransform and KStream.flatTransformValues (partially implemented; completed in 2.3)
KIP-393: Time windowed serde to properly deserialize changelog input topic
KIP-319: Replace segments with segmentInterval in WindowBytesStoreSupplier
KIP-321: Update TopologyDescription to better represent Source and Sink Nodes
KIP-328: Ability to suppress updates for KTables (partially implemented; not completed yet → inactive)
KIP-358: Migrate Streams API to Duration instead of long ms times
KIP-365: Materialized, Serialized, Joined, Consumed and Produced with implicit Serde
Kafka 0.10.1:
Kafka 0.10.0:
KIP-378: Enable Dependency Injection for Kafka Streams handlers
KIP-406: GlobalStreamThread should honor custom reset policy