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GraphQL

Query-first APIs. Schemas, resolvers, and clients.

Browse 30 tutorials → Other topics

Why learn GraphQL?

  • Clients ask for exactly the data they need, nothing more.

  • A single endpoint that aggregates multiple data sources.

  • Strong typing across the wire — great with TypeScript.

  • A frontend-friendly alternative to REST for complex UIs.

What you can build with GraphQL

Mobile and SPA backends BFF (backend for frontend) layers Aggregating microservices Public APIs with diverse clients

GraphQL tutorials

30 articles · page 1 of 2

Hand-written tutorials, ordered as a recommended learning path.

  1. 01 What Is GraphQL? A clear introduction to GraphQL — a single endpoint, exact-fields queries, a typed schema, and how it compares to REST. Learn when GraphQL fits and when it doesn't.
  2. 02 Schemas & Resolvers A practical guide to GraphQL schemas — SDL, scalar types, Query and Mutation roots, custom object types, resolver functions, and how to avoid the N+1 problem with DataLoader.
  3. 03 Auth & Authorization Implement secure auth in GraphQL using context-based authentication, custom directives, and field-level permission patterns.
  4. 04 Error Handling Patterns Implement robust error handling in GraphQL using error extensions, union-based result types, and structured error responses.
  5. 05 Federation & Microservices Build a unified GraphQL API from multiple microservices using Apollo Federation, subgraphs, and gateway composition.
  6. 06 Testing Strategies Test GraphQL APIs effectively with unit tests for resolvers, integration tests against the schema, and end-to-end mocking strategies.
  7. 07 Caching Strategies Master GraphQL caching with client-side normalized caches, persisted queries, CDN caching, and server-side response caching.
  8. 08 File Uploads Implement file uploads in GraphQL using multipart requests, presigned URLs, and streaming patterns for production-ready file handling.
  9. 09 Pagination Patterns Master GraphQL pagination with cursor-based and offset-based approaches, Relay-style connections, and infinite scroll implementation.
  10. 10 Subscriptions & Real-Time Build real-time features with GraphQL subscriptions using WebSockets, PubSub engines, and scalable event-driven architectures.
  11. 11 Code Generation & TypeScript Automate type-safe GraphQL development using graphql-codegen to generate TypeScript types, hooks, and resolvers from your schema.
  12. 12 DataLoader & N+1 Learn how the DataLoader pattern batches and caches database calls to eliminate N+1 query performance issues in GraphQL APIs.
  13. 13 Cursor vs Offset Pagination Compare cursor-based and offset-based pagination in GraphQL, and implement the Relay connection specification for scalable lists.
  14. 14 Query Complexity & Depth Protect your GraphQL API from expensive queries using query complexity scoring, depth limiting, and cost analysis techniques.
  15. 15 Schema Design Patterns Master GraphQL schema design with practical patterns for naming, nullability, input types, enums, and evolving schemas without versioning.
  16. 16 Subscriptions & Real-Time Build real-time features with GraphQL subscriptions using WebSockets, including setup with Apollo Server and client-side integration.
  17. 17 Resolvers Guide Master GraphQL resolvers: resolver functions, context, the N+1 problem, DataLoader for batching, error handling, authorization in resolvers, and performance patterns.
  18. 18 Schema Design Design GraphQL schemas that scale: types, queries, mutations, connections, pagination, nullability, naming conventions, and patterns for evolving your API over time.
  19. 19 Apollo Cache How Apollo Client's normalized cache works, why entity IDs matter, and the patterns for cache updates, refetches, and consistent UI after mutations.
  20. 20 GQL Errors Compare the errors array, union result types, and partial responses to design predictable, typed error handling for your GraphQL APIs and clients.