Apollo Server
By Apollo GraphQL, Inc.
js that lets developers define a schema and resolvers to build production-ready GraphQL APIs, as part of the broader Apollo GraphQL platform.
Definition
Apollo Server is an open-source, spec-compliant GraphQL server library for Node.js that lets developers define a schema and resolvers to build production-ready GraphQL APIs, as part of the broader Apollo GraphQL platform.
Overview
Apollo Server implements the official GraphQL specification on top of Node.js, and can run as standalone middleware or be mounted onto existing HTTP frameworks such as Express.js or Fastify. Development follows a schema-first approach: developers define types and operations using GraphQL's Schema Definition Language (SDL), then write resolver functions that fetch or compute the data for each field. Beyond basic query execution, Apollo Server supports Apollo Federation, letting a service act as one "subgraph" that gets composed with others into a larger unified API managed by Apollo GraphQL's gateway. Its plugin system adds capabilities like response caching, performance tracing, and custom error formatting, and it includes TypeScript support along with an interactive schema explorer (Sandbox) for testing queries during development. Apollo Server is commonly paired with Apollo Client or other GraphQL clients consuming the API from React or other frontend applications.
Key Features
- Spec-compliant GraphQL query execution engine
- Schema-first development with SDL and resolver functions
- Integrates with Express, Fastify, or runs standalone
- Apollo Federation support for building composable subgraphs
- Plugin system for caching, tracing, and error handling
- First-class TypeScript support
- Built-in schema explorer for interactive testing
Use Cases
Frequently Asked Questions
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