GraphQL Federation

Purpose

Design and implement GraphQL Federation: compose multiple subgraphs into a unified supergraph, manage distributed GraphQL architecture, and scale GraphQL across teams. Make informed build-vs-buy decisions between Apollo Federation and alternative distributed graph strategies.

Workflow

Federation Architecture

Supergraph (Apollo Router / Gateway)
  ├── Subgraph A (Users service) — @key(fields: "id")
  ├── Subgraph B (Orders service) — @key(fields: "id") @extends User
  ├── Subgraph C (Reviews service) — @key(fields: "id") @extends User
  └── Subgraph D (Inventory service) — standalone

Apollo Federation vs. GraphQL Mesh Decision Tree

Use this decision framework when choosing between Apollo Federation and GraphQL Mesh: