Apache Polaris is an open-source catalogue for Apache Iceberg tables and for other data and AI assets. It implements the Iceberg REST catalogue API, so query engines such as Apache Spark, Apache Flink, Trino and Dremio OSS can work on the same tables, and it offers an open alternative to proprietary lakehouse catalogues. The documentation covers JDBC and PostgreSQL backends, Keycloak authentication and Prometheus or Jaeger telemetry. The software is licensed under the Apache License 2.0 and is run by the operator on its own infrastructure.
The project is developed under the Apache Software Foundation, a US 501(c)(3) non-profit, so US jurisdiction can reach the organisation behind the project even though the code is open. The catalogue holds table metadata, while storage backends such as Apache Ozone, Ceph or RustFS are configured separately by the operator. For a European organisation, sovereignty therefore depends on where those storage and identity components run and on whether the operator keeps the deployment under its own control.