GraphQL Foundations
What GraphQL is, the type system & SDL, and the request lifecycle. Start →
GraphQL Design — From Zero to Hero
A standalone, beginner→advanced course on designing GraphQL APIs, taught with TypeScript. From the type system to schema design, resolvers, Relay pagination, the N+1 problem, security, and federation — with queries that actually execute in the browser.
What you’ll learn
Section titled “What you’ll learn”Schema Design
Types, scalars, enums, interfaces, unions, inputs, and nullability. Design →
Queries & Resolvers
Queries, the resolver chain, arguments & variables, fragments. Resolve →
Mutations & Subscriptions
Mutation design, the input/payload pattern, real-time subscriptions. Write →
Pagination & Relationships
Relay cursor connections, relationships, the N+1 problem & DataLoader. Page →
Errors & Validation
The errors array, partial results, error extensions, input validation. Handle →
Security & Performance
Auth via context, authorization, depth/complexity limiting, caching. Secure →
Tooling, Federation & Building
Schema-first vs code-first, codegen, testing, federation, GraphQL Yoga. Ship →
How this course works
Section titled “How this course works”GraphQL runs in your browser
Queries and mutations execute live against in-memory schemas (the reference implementation), and full GraphQL Yoga servers open in StackBlitz.
Diagrams that explain
The request lifecycle, the resolver chain, the Relay connection model, and federation as theme-aware Mermaid diagrams.
Design, not just syntax
Every topic covers the why and the trade-offs — schema choices, the N+1 problem, error shapes, and securing a flexible endpoint.
Bilingual + read mode
English and ไทย, quizzes with saved progress, and a distraction-free read mode.
Versions checked
Section titled “Versions checked”This course’s facts, APIs, and code were checked against these versions as of September 2026: GraphQL spec September 2025 edition (@oneOf input unions are now stable; @defer/@stream are still a Stage 1 RFC, not in the spec), graphql-js 16.x stable (v17, with experimental incremental delivery, is not yet GA), Apollo Server 5.x, GraphQL Yoga 5.x, and the GraphQL over HTTP spec (application/graphql-response+json). Runnable code samples execute against these versions; every “real-world example” links to its primary source.