Event streaming · Apache Software Foundation
Apache Pulsar
Open-source, cloud-native distributed messaging and streaming platform with built-in multi-tenancy and geo-replication.
Apache Pulsar is a distributed pub-sub messaging system that separates the serving layer (brokers) from the storage layer (Apache BookKeeper), which lets each scale independently and gives Pulsar native support for very large numbers of topics (up to a million per cluster) and built-in multi-tenancy across teams or customers. It supports both traditional queuing and Kafka-style stream consumption patterns from the same topic type, geo-replication across clusters, and tiered storage that offloads older segments to object storage to control cost. As a foundation project it is entirely free and open source with no vendor pricing of its own; managed offerings and enterprise support come from third-party vendors such as StreamNative. It's a common alternative to Kafka for teams needing native multi-tenancy or geo-replication out of the box.
At a glance
| Vendor | Apache Software Foundation |
|---|---|
| Pricing model | Open source + paid options |
| Free tier | Yes |
| Deployment | Self-hosted |
| Open source | Yes (Apache-2.0) |
| Best for | Teams needing native multi-tenancy or geo-replication in a self-hosted streaming platform. |
Pricing
Free and open source with no vendor pricing; managed hosting and support are offered by third-party vendors, not the Apache project itself.
Pricing has not been verified yet — see the vendor's site.
Features
- Separated compute (brokers) and storage (BookKeeper) layers
- Native multi-tenancy
- Built-in geo-replication
- Support for up to a million topics per cluster
- Unified queuing and streaming consumption model
- Tiered storage offload to object storage
Integrations
Profile last reviewed September 21, 2026