WunderGraph provides an open-source, design-first platform to compose GraphQL from heterogeneous data sources (REST/OpenAPI, GraphQL, SQL/NoSQL, and more) using a virtual graph with a query planner and execution engine written in Go. It supports schema stitching, federation, and namespacing to avoid collisions, enabling unified APIs with built-in RBAC and code‑as‑config workflows. WunderGraph Cosmo extends this with a full lifecycle platform for monolithic and federated GraphQL: a schema registry with versioning and checks, a high‑performance router supporting Federation v1 and v2, analytics, metrics, tracing, access control, and PR-based schema workflows; it is available self‑hosted or as a managed service under Apache 2.0.

Key Features

Multi‑source GraphQL composition Unify REST, databases, and services into one graph.

• Data sources: REST/OpenAPI, GraphQL, SQL (PostgreSQL, MySQL, SQLite, SQLServer), MongoDB, and more
• Query planner and execution engine in Go for flexible resolver logic

Collision‑free schema stitching Combine APIs safely.

• API namespacing to avoid type/field naming collisions during composition

Cross‑API joins and federation options Model data relationships across systems.

• Cross API joins with support for schema stitching and federation models
• Works with Apollo Federation sources and monolithic graphs

Built‑in RBAC and secure gateway Protect unified APIs.

• Role‑based access controls integrated into the platform
• Centralized routing and policy enforcement via Cosmo router

Cosmo Schema Registry and checks Govern change with confidence.

• Schema registry for monographs and Federation v1/v2
• Composition checks, breaking change detection, client traffic checks, and linting checks

Operations, analytics, and DX Operate and iterate at scale.

• Metrics, tracing, analytics, and routing for federated graphs
• Pull request–based schema composition workflows and changelogs

Benefits

Faster API delivery across heterogeneous backends

• Compose a unified graph from REST/GraphQL/DBs without building custom clients
• Namespacing and planner reduce manual glue code and collisions

Stronger governance and safer changes

• Registry with automated composition and breaking change checks
• Client traffic–aware validation to minimize disruptive releases

Operational visibility and flexibility

• Tracing, metrics, analytics, and high‑performance routing for monolithic or federated topologies
• Open source with self‑hosted or managed options to avoid lock‑in