• Instrument the start of message/batch processing (#496).
• Mark Client#fetch_messages as stable.
• Fix the list topics API (#508).
• Add support for LZ4 compression (#499).
• Refactor compression codec lookup (#509).
• Fix compressed message set offset bug (#506).
• Test against multiple versions of Kafka.
• Fix double-processing of messages after a consumer exception (#518).
• Track consumer offsets in Datadog.