Google Cloud Pub/Sub vs WarpStream BYOC Schema Registry

Google Cloud Pub/Sub is a cloud messaging service for asynchronous communication between services that produce messages and those that process them. It is intended for service-to-service use, including streaming analytics, data integration, middleware, and parallel task queues, rather than direct communication with end users or IoT clients. Communication typically has latency around 100 milliseconds. Synchronous cross-zone replication and per-message receipt tracking provide at-least-once delivery; Dataflow supports exactly-once processing of Pub/Sub streams. There are no shards or partitions, and provisioning scales automatically after quota is set. Message controls include seek and replay, dead letter topics, and attribute-based filtering. Pub/Sub offers fine-grained access controls, end-to-end encryption, and HIPAA compliance. It supports REST and gRPC APIs and client libraries for seven languages; API keys are not supported for authentication. The maximum message size is 10 MB. The free monthly tier is free for the first 10 GB of data per month. Pay-as-you-go is $40 a month beyond 10 GB, with throughput listed at $40 per TB and storage at $0.27 per GiB-month.

WarpStream BYOC Schema Registry stores and serves schemas for Kafka records through a REST server compatible with Confluent’s Schema Registry API. It supports Avro and protobuf, while WarpStream Agents validate records and can reject invalid data or emit metrics. The stateless, zero-disk registry stores schemas in the customer’s object storage, and WarpStream says they remain in that cloud account. Schema Linking migrates schemas from a Confluent-compatible registry while preserving IDs and compatibility rules. Authentication options include Basic Authentication, TLS and mutual TLS. Customers create a Schema Registry Virtual Cluster in the console or API, then deploy an agent using the Kafka Agents binary; agents emit logs and metrics. Each registry allows 100,000 schema versions and each schema 1 MB, with support-requested increases. Plans are Dev at $0.03 a month, Fundamentals at 0.17 USD, Pro at 0.52 USD, and Enterprise with no listed price. Cluster minutes use 15-minute billing intervals.