Druid 0.9.1-rc4 available

We’re happy to announce our next release candidate, Druid 0.9.1-rc4!

Druid 0.9.1 will contain hundreds of performance improvements, stability improvements, and bug fixes from over 30 contributors. Major new features include an experimental Kafka Supervisor to support exactly-once consumption from Apache Kafka, support for cluster-wide query-time lookups (QTL), and an improved segment balancing algorithm.

This release candidate revives the deprecated druid-namespace-lookup extension, which is intended to help users migrate to the new QTL framework by making it possible to deploy both the old and new frameworks simultaneously. See the draft release notes for details on migration. This release candidate also includes a few fixes and documentation updates. Thanks to everyone who tested our previous release candidates.

You can download the release candidate here:


Draft release notes are at:


Please file GitHub issues here if you find any problems with the release candidate:


Thanks to all of you who contributed issues, docs, and code!