Amazon AppSync vs WunderGraph Cosmo

Amazon AppSync has no write-up on Specifiction yet; its figures are above.

WunderGraph Cosmo is an open-source GraphQL Federation platform for platform teams, offering schema checks, guardrails and observability. It unifies GraphQL, REST, gRPC and Kafka in a federated graph and supports Apollo Federation versions 1 and 2 across existing GraphQL services. Cosmo Router is a Go-based, Apache 2.0-licensed router and gateway. Teams can deploy it with Docker, Kubernetes or an AWS Lambda-optimized binary, or use WunderGraph’s managed service. The Schema Registry checks composition, breaking changes, client traffic and linting. Subscriptions work over WebSockets and Server-Sent Events, and event-driven subscriptions can use Kafka, NATS, SQS or RabbitMQ. Cosmo Streams supports Kafka, NATS including JetStream, and Redis. Observability includes OpenTelemetry tracing and Prometheus metrics, which can be exported to compatible backends. The free Developer plan includes one federated graph, 10M requests/month, 10 subgraphs, one team member and seven-day retention. Launch costs $499 a month; Scale costs $3,499 a month. Enterprise pricing is custom. Managed plans include SOC 2 and HIPAA compliance; the site also identifies ISO 27001 certification.