## Description:
Pulsar is a highly scalable, low latency messaging platform running on
commodity hardware. It provides simple pub-sub semantics over topics,
guaranteed at-least-once delivery of messages, automatic cursor management for
subscribers, and cross-datacenter replication.
## Project Status:
- There are no issues requiring board attention at this time.
## Project Activity:
- Work on the 5.0.0-M1 release is well underway. This will be the first
preview of Pulsar 5, introducing the new Scalable Topics API — the
culmination of the multi-PIP "Topics v5" initiative described below.
- Pulsar 4.2.0, the latest feature release, was released on March 31st
2026. Maintenance releases across the 4.2.x, 4.0.x, and 3.0.x lines
continue on a regular cadence:
- 4.2.2 was released on June 8th 2026
- 4.0.11 was released on June 8th 2026
- 4.2.1 was released on April 27th 2026
- 4.0.10 was released on April 27th 2026
- 3.0.17 was released on April 27th 2026
- 4.2.0 was released on March 31st 2026
- 4.1.3 was released on February 19th 2026
- 4.0.9 was released on February 19th 2026
- 3.0.16 was released on February 16th 2026
- Pulsar C++ releases:
- 4.2.0 on June 14th 2026
- 4.1.0 on March 30th 2026
- Pulsar Go releases:
- 0.19.0 on April 15th 2026
- Pulsar Python releases:
- 3.12.0 on May 20th 2026
- 3.11.0 on April 16th 2026
- Pulsar NodeJS releases:
- 1.17.0 on April 9th 2026
- We continue to have a very high number of "Pulsar Improvement
Proposal" being submitted, discussed and voted by the community.
This quarter was exceptionally active, with nearly 30 PIPs seeing
activity (PIP-457 through PIP-485) — roughly double the previous
quarter. A major theme is the multi-PIP "Scalable Topics (Topics v5)"
initiative, which introduces topics that scale elastically while
preserving key ordering (PIP-460, 466, 468, 473, 475, 483) and which
will ship as a preview in Pulsar 5.0.0-M1, alongside a broad
platform-modernization effort (PIP-457, 462, 463, 465, 467, 472).
A selection:
PIP-457: Remove support for V1 topic names and V1 Admin API
PIP-460: Scalable Topics (Topics v5)
PIP-462: Remove Etcd metadata store backend
PIP-463: Migrate Build System from Maven to Gradle
PIP-464: Deprecate legacy Jackson JsonSchema format for SchemaType.JSON
PIP-465: Split IO Connectors into Separate Repository
PIP-466: New Java Client API (V5) with Scalable Topic Support
PIP-467: Adopt slog for structured logging across Pulsar
PIP-468: Scalable Topic Controller
PIP-469: Legacy-aware topic policies backend routing and
metadata-store topic policies
PIP-470: Close inactive topics without deleting their data
PIP-471: Authorization operation metrics
PIP-472: Migrate from javax.* to jakarta.* APIs
PIP-473: Metadata-Driven Transactions for Scalable Topics
PIP-474: Key_Shared Hot Key Overflow Mechanism
PIP-475: Regular-to-Scalable Topic Migration
PIP-476: Extensible Key_Shared Dispatcher Mechanism
PIP-477: Dynamic Bookie Cluster Switching for Brokers
PIP-478: Asynchronous v5 client auth plugin and TLS material
provider plugin interfaces
PIP-480: Add readEntries method to ManagedLedger
PIP-481: Retain Ended Transaction Status for Precise Error Reporting
PIP-482: Peek messages from topic subscription with messagePosition
PIP-483: Scalable Topic Auto Split/Merge
PIP-484: Expose incremental window events via IncrementalWindowFunction
PIP-485: Configurable mTLS principal mapping
- Pulsar has reached 724 contributors on the main GitHub repo
(It was 712 in February 2026)
## Health report:
- There is healthy growth in the community, and several users are starting
to become contributors to the project and engage more and more with
the community. The volume of Pulsar Improvement Proposals and the
associated dev@ list discussion grew markedly this quarter, driven in
large part by the Scalable Topics initiative leading up to the Pulsar 5
preview.
## Membership Data:
Apache Pulsar was founded 2018-09-18 (7 years ago)
There are currently 85 committers and 47 PMC members in this project.
The Committer-to-PMC ratio is roughly 2:1.
Community changes, past quarter:
- No new PMC members. Last addition was Cong Zhao on 2025-09-16.
- No new committers. Last addition was Mingze Han on 2025-07-05.
## Community Health:
- Activity on the mailing lists remains high with a mixture of new users,
contributors, and deeper, more experienced users and contributors sparking
discussion and questions and filing bugs or new features.
- [email protected]:
- 15% increase in traffic in the past quarter (15 emails compared to 13)
- [email protected]:
- 82% increase in traffic in the past quarter (319 emails compared to 175)
## Slack activity:
- 10910 Members (10852 in February 2026)
- 133 Active monthly users (162 in February 2026)
--
Matteo Merli
<[email protected]>
