Apache Paimon is a lake format for streaming and batch workloads with Flink and Spark. Append and primary-key tables share versioned snapshots and manifest-based file management. Primary-key tables use an LSM-based layout for streaming updates. Append tables can enable Data Evolution to align column files by row ID and update selected columns while retaining files for untouched columns. Data Evolution uses positional column merging independently of primary-key LSM merging.

Background and documentation are available at https://paimon.apache.org

Paimon's former name was Flink Table Store, developed from the Flink community. The architecture refers to some design concepts of Iceberg. Thanks to Apache Flink and Apache Iceberg.

Collaboration

Paimon tracks issues in GitHub and prefers to receive contributions as pull requests.

Mailing Lists

Please make sure you are subscribed to the mailing list you are posting to! If you are not subscribed to the mailing list, your message will either be rejected (dev@ list) or you won't receive the response (user@ list).

Slack

You can join the Paimon community on Slack. Paimon channel is in ASF Slack workspace.

• Anyone with an @apache.org email address can become a full member of the ASF Slack workspace. Search Paimon channel and join it.
• If you don't have an @apache.org email address, you can email to user@paimon.apache.org to apply for an ASF Slack invitation. Then join Paimon channel.

Building

JDK 8/11 is required for building the project. Maven version >=3.6.3.

• Run the mvn clean install -DskipTests command to build the project.
• Run the mvn spotless:apply to format the project (both Java and Scala).
• IDE: Mark paimon-common/target/generated-sources/antlr4 as Sources Root.

How to Contribute

Contribution Guide.

License

The code in this repository is licensed under the Apache Software License 2.