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Licence terms can change between releases, so verify against the repository for the version you intend to use.","source":"https://github.com/apache/pulsar","question":"Is Apache Pulsar open source?","confidence":0.95}],"faqSource":"generated","releaseHistory":[{"version":"v4.2.4","date":"2026-08-03T09:19:30Z","url":"https://github.com/apache/pulsar/releases/tag/v4.2.4","type":"stable"},{"version":"v4.0.13","date":"2026-08-03T09:19:06Z","url":"https://github.com/apache/pulsar/releases/tag/v4.0.13","type":"stable"},{"version":"v4.2.3","date":"2026-07-06T08:46:50Z","url":"https://github.com/apache/pulsar/releases/tag/v4.2.3","type":"stable"},{"version":"v4.0.12","date":"2026-07-06T08:46:18Z","url":"https://github.com/apache/pulsar/releases/tag/v4.0.12","type":"stable"},{"version":"v5.0.0-M1","date":"2026-06-23T14:11:26Z","url":"https://github.com/apache/pulsar/releases/tag/v5.0.0-M1","type":"prerelease"},{"version":"v4.2.2","date":"2026-06-08T18:16:45Z","url":"https://github.com/apache/pulsar/releases/tag/v4.2.2","type":"stable"},{"version":"v4.0.11","date":"2026-06-08T18:16:01Z","url":"https://github.com/apache/pulsar/releases/tag/v4.0.11","type":"stable"},{"version":"v4.2.1","date":"2026-04-27T13:04:33Z","url":"https://github.com/apache/pulsar/releases/tag/v4.2.1","type":"stable"},{"version":"v4.0.10","date":"2026-04-27T13:04:17Z","url":"https://github.com/apache/pulsar/releases/tag/v4.0.10","type":"stable"},{"version":"v3.0.17","date":"2026-04-27T13:03:58Z","url":"https://github.com/apache/pulsar/releases/tag/v3.0.17","type":"stable"},{"version":"v4.2.0","date":"2026-03-31T21:12:26Z","url":"https://github.com/apache/pulsar/releases/tag/v4.2.0","type":"stable"},{"version":"v4.1.3","date":"2026-02-19T19:48:49Z","url":"https://github.com/apache/pulsar/releases/tag/v4.1.3","type":"stable"},{"version":"v4.0.9","date":"2026-02-19T19:48:13Z","url":"https://github.com/apache/pulsar/releases/tag/v4.0.9","type":"stable"},{"version":"v3.0.16","date":"2026-02-16T09:24:53Z","url":"https://github.com/apache/pulsar/releases/tag/v3.0.16","type":"stable"},{"version":"v4.1.2","date":"2025-11-17T07:58:34Z","url":"https://github.com/apache/pulsar/releases/tag/v4.1.2","type":"stable"},{"version":"v4.0.8","date":"2025-11-17T07:58:06Z","url":"https://github.com/apache/pulsar/releases/tag/v4.0.8","type":"stable"},{"version":"v3.0.15","date":"2025-11-17T07:57:45Z","url":"https://github.com/apache/pulsar/releases/tag/v3.0.15","type":"stable"},{"version":"v4.1.1","date":"2025-09-27T04:40:25Z","url":"https://github.com/apache/pulsar/releases/tag/v4.1.1","type":"stable"},{"version":"v4.0.7","date":"2025-09-27T04:40:06Z","url":"https://github.com/apache/pulsar/releases/tag/v4.0.7","type":"stable"},{"version":"v3.3.9","date":"2025-09-27T04:39:25Z","url":"https://github.com/apache/pulsar/releases/tag/v3.3.9","type":"stable"}],"integrations":[{"name":"Kafka"},{"name":"RabbitMQ"},{"name":"MongoDB"},{"name":"Cassandra"},{"name":"Elasticsearch"},{"name":"HBase"},{"name":"HDFS"},{"name":"InfluxDB"},{"name":"Redis"},{"name":"Solr"},{"name":"DynamoDB"},{"name":"Kinesis"},{"name":"Azure Data Explorer"},{"name":"ClickHouse"},{"name":"PostgreSQL"},{"name":"MariaDB"},{"name":"SQLite"},{"name":"Debezium MySQL"},{"name":"Debezium PostgreSQL"},{"name":"Debezium MongoDB"},{"name":"Debezium Oracle"},{"name":"Debezium Microsoft SQL Server"},{"name":"Canal"},{"name":"Aerospike"},{"name":"Alluxio"},{"name":"NSQ"},{"name":"Netty"},{"name":"HTTP"},{"name":"File"},{"name":"Kafka Connect Adaptor","direction":"bidirectional","native":true}],"vulnerabilities":{"count":1,"last12m":0,"maxSeverity":"MODERATE","source":"https://advisories.ecosyste.ms/api/v1/advisories?ecosystem=maven&package_name=org.apache.pulsar%3Apulsar-client&per_page=100"},"claimed":false,"updatedAt":"2026-09-14T09:34:00.761Z","formats":{"json":"https://www.vioscale.ai/api/v1/software/apache-pulsar","markdown":"https://www.vioscale.ai/software/apache-pulsar.md","html":"https://www.vioscale.ai/software/apache-pulsar"}},"meta":{"source":"https://www.vioscale.ai","license":"CC-BY-4.0","generatedAt":"2026-09-21T01:30:30.871Z","disclaimer":"Independent, evidence-based. 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