GraphQL Federation lets multiple NestJS microservices expose @key entities that a central gateway stitches together into one unified schema—perfect for enterprise API gateways handling complex domain data.​
Each subgraph service uses ApolloFederationDriver with @key(fields: "id") directives on entities, while the gateway uses ApolloGatewayDriver to compose the supergraph. NestJS v10+ makes this seamless with code-first or schema-first approaches.
Subgraph service:
Gateway service:
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