Apache Pulsar vs StreamHouse

Apache Pulsar is a free, open-source distributed messaging and streaming platform built for cloud use. It supports message consumption with less than 10 ms latency and up to one million unique topics in a cluster. Configurable replication across geographic regions and automatic client failover to healthy clusters support multi-region deployments. Tenants and policies control access to data and actions, and can isolate brokers to limit noisy-neighbor effects. Maintained client libraries are available for Java, Go, Python, C++, Node.js, and C#. Built-in connectors move data to and from systems including Kafka, RabbitMQ, MySQL, PostgreSQL, MongoDB, Cassandra, and Elasticsearch. Pulsar Functions process messages with user-defined logic in Java, Python, or Go. Tiered storage can offload data from BookKeeper to blob storage such as S3 for unlimited retention. It can run in Docker or Kubernetes, with a Helm chart for Kubernetes. Encryption, authentication, and authorization are available but are not enabled by default. The 5.0.0-M2 milestone is for early testing and feedback, not production use.

StreamHouse is an open-source, self-hostable system combining event streaming, processing, schema management, and observability. Developers can ingest events through REST, gRPC, or the Kafka protocol, then use its SQL engine to query streams and transform events in pipelines. Pipelines can continuously send SQL-transformed results to PostgreSQL and be managed through the CLI or an SDK. StreamHouse stores data in S3 and describes that storage as S3-native. Its schema registry supports JSON Schema, Avro, and Protobuf with compatibility checking. Listed sinks include PostgreSQL, S3, and Elasticsearch. Monitoring includes Prometheus metrics, Grafana dashboards, and real-time WebSocket metrics. Organization-scoped isolation and permissioned API keys provide access controls. Python and TypeScript SDKs are documented, while CLI installation is available through Homebrew or a shell installer. The project uses Apache License 2.0, and its stateless agents can scale like web servers.