Lakestream

COMMUNITY

Community

Lakestream is developed in the open on GitHub. Questions and ideas go to GitHub Discussions, changes land as pull requests, and changes that other people build on (an API, an SPI, a storage format) start as a Lakestream Improvement Proposal.

Where to talk

The projects don't run a Slack workspace or a mailing list, so decisions happen where everyone can read them.

Contribute

Every repository takes issues and pull requests. Sign off each commit with git commit -s (the Developer Certificate of Origin); there's no CLA. The contributor guide covers the rest.

Ursa

openlakestream/ursa

The storage engine, the lakestream-api module, and materializers.

Ursa for Apache Kafka

openlakestream/kafka

Diskless topics and the Ursa integration. Problems that also happen on Apache Kafka belong upstream.

Improvement proposals

openlakestream/lips

Design proposals for the Lakestream API, SPI contracts, storage formats, and the contract between Kafka and Lakestream.

streaming-proof

openlakestream/streaming-proof

The black-box harness that checks delivery and ordering on a running system.

leaderless-log-protocol

openlakestream/leaderless-log-protocol

Protocol specifications and their TLA+ and Fizzbee models. A protocol change starts with the spec.

Proposals (LIPs)

A Lakestream Improvement Proposal is a short design document for a change that other people build on or operate against: the Lakestream API, an SPI contract, a storage format, or the contract between Kafka and Lakestream. Bug fixes, refactoring, performance work that keeps behavior and formats unchanged, tests and documentation don't need one.

LIPTitleStatus
LIP-161Table Materialization FrameworkReleased in Ursa 1.0
LIP-162Diskless Storage with Ursa IntegrationReleased in UFK 4.3.1
LIP-163Ursa Zone-Aware Owner SelectionReleased in UFK 4.3.1
How LIPs work →

Roadmap

LIPs in progress, and ideas the maintainers and the LIPs have written down. An idea isn't scheduled work, and it may not have a LIP yet.

In progress

No LIP is in progress right now.

Ideas

  • Ursa for Apache Kafka (UFK)3 ideas
  • Stream materialization framework7 ideas
  • Build on Lakestream3 ideas
  • Further out1 idea
See the roadmap →

Talks and papers

  • Ursa: A Lakehouse-Native Data Streaming Engine for Kafka

    PVLDB 18(12) · VLDB 2025 Best Industry Paper

    Read the paper
  • Data Streaming Summit 2026 keynote

    October 8, 2026 · San Francisco

Governance

Lakestream is stewarded by StreamNative. Each repository's maintainers are the code owners in its CODEOWNERS file, and a LIP is accepted when its pull request in openlakestream/lips merges.