// the find
wundergraph/cosmo
The open-source solution to building, maintaining, and collaborating on GraphQL Federation at Scale. The alternative to Apollo Studio and GraphOS.
Cosmo is a self-hostable GraphQL Federation platform — schema registry, composition checks, a router, and observability — pitched as the open-source alternative to Apollo GraphOS. It's for teams already running federated GraphQL at real scale who want to own the control plane instead of paying Apollo, not for someone federating their first two services.
The performance claims are backed by actual engineering writeups (Super Bowl traffic scaling, epoll/kqueue-based subscription handling, a custom AST minification algorithm), not just blog fluff. Deployment story is genuinely complete — Helm chart, Docker Compose, Terraform, and a CLI with real subcommands for graphs, subgraphs, contracts, feature flags, and proposals, not a thin wrapper. The router plugin system scaffolds working Go and TypeScript plugin projects (Dockerfile, Makefile, tests included) rather than just exposing a config file.
The README is almost entirely marketing copy — 'comprehensive', 'tailored', 'empowers' — with zero inline code or query examples; the actual quickstart is an outbound link. GitHub tags the repo as TypeScript, but the router itself is Go per the linked blog posts, and the monorepo also contains a separate admission-server, cdn-server, keycloak setup, and an aws-lambda-router — a contributor needs to context-switch across several stacks just to make one change. It's open-core: the README leads with login links to the managed cloud and a sales contact for 'decision makers', so expect the self-hosted path to get less documentation and support attention than the paid one. At ~1.2k stars for something claiming Super Bowl-scale production use, it's worth checking how many of those deployments are actually self-hosted versus the managed service.