Open source for data and AI

Projects749Relicensed100

749 projects · 100 relicensed

ksqlDB license, foundation and stars

Streaming · Confluent Community License Agreement 1.0 (source-available) · backed by Confluent · 316 stars

GitHub

The database purpose-built for stream processing applications.

License history

LICENSE file
Source-availableDec 14, 2018

Apache 2.0 to Confluent Community License Agreement 1.0

KSQL moved from Apache 2.0 to the Confluent Community License, which bars competing SaaS offerings.

AnnouncementLICENSE commit ↗

Latest release

No GitHub releases published; the project releases elsewhere (tags or its own site).

More in streaming

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ProjectStars
Apache KafkaApache Kafka - A distributed event streaming platform.ApacheApache 2.034.1k
Apache FlinkAn event streaming project at the Apache Software Foundation, written in Java.ApacheApache 2.026.5k
nsqA realtime distributed messaging platform.MIT25.8k
Apache RocketmqApache RocketMQ is a cloud native messaging and streaming platform, making it simple to build event-driven applications.Apache 2.022.7k
nats-serverHigh-Performance server for NATS.io, the cloud and edge native messaging system.Apache 2.021k
EMQXThe most scalable and reliable MQTT broker for AI, IoT, IIoT and connected vehicles.EMQ TechnologiesBUSL 1.116.9k
Apache PulsarApache Pulsar - distributed pub-sub messaging system.Apache 2.015.4k
rabbitmq-serverOpen source RabbitMQ: core server and tier 1 (built-in) plugins.Custom or mixed (see the LICENSE file)14k
About and history
Repository
confluentinc/ksql · created Sep 27, 2016
Website
ksqldb.io
Language
Java
Foundation
None; run by Confluent
Company
Confluent · on Companies · on Acquisitions · on awards · on blogs · on certifications · on Attested · on Downtime · on Mainstage · on Leaders · on marketplaces · on Paydays · on Footprint · on Releases · on Nines · on Stories · on TechConf · on Titlewave · on training
GitHub detects
NOASSERTION (a custom or multi-license file; the license above is read from the file itself)
Stars per week
0 (GitHub weekly snapshots)

Weekly snapshots

Week ofStars
Oct 26, 2026316
Oct 19, 2026316
Oct 12, 2026316
Sep 28, 2026315
Sep 21, 2026315

Changes

Stars per weekOct 3, 2026

Gains about 0 stars a week.

RelicensedSep 25, 2026

Relicensed from Apache 2.0 to Confluent Community License Agreement 1.0.

TrackedSep 25, 2026

Now tracked, from confluentinc/ksql on GitHub.