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graphql/graphql-js

📈 Trending★ 20,315TypeScriptAudience · developerComplexity · 3/5ActiveLicenseSetup · easy

TLDR

Official JavaScript implementation of GraphQL, a query language that lets clients request exactly the data they need from a server in a single query.

Mindmap

mindmap
  root((repo))
    What it does
      Parse GraphQL queries
      Validate against schema
      Execute resolvers
      Return exact data
    Core concepts
      Type schema definition
      Resolver functions
      Query validation
      Single request model
    Use cases
      Build custom servers
      Low-level control
      Browser environments
      Node.js backends
    Tech stack
      TypeScript
      JavaScript
      npm package
    Audience
      Backend developers
      API builders
      Framework authors

Things people build with this

USE CASE 1

Build a custom GraphQL server that validates queries and executes resolver functions to return exactly the data clients request.

USE CASE 2

Add GraphQL support to a Node.js or browser application without relying on a higher-level framework like Apollo Server.

USE CASE 3

Define a type schema describing your application's data types and relationships, then parse and validate incoming GraphQL queries against it.

USE CASE 4

Integrate GraphQL into an existing API to let clients fetch multiple related resources in a single request instead of making multiple REST calls.

Tech stack

TypeScriptJavaScriptNode.js

Getting it running

Difficulty · easy Time to first run · 5min
Use freely for any purpose, including commercial use, as long as you keep the copyright notice.

In plain English

GraphQL.js is the official JavaScript reference implementation of GraphQL, the query language for APIs originally created by Facebook. GraphQL itself is a way for client applications to ask a server for exactly the data they need, no more, no less, in a single request. Rather than calling multiple different REST endpoints and stitching responses together, a GraphQL client sends one query describing the exact shape of data it wants, and the server responds with just that structure. This library is the JavaScript/TypeScript engine that makes that possible on the server side. Using it, a developer first defines a "type schema", a description of all the data types their application exposes and how they relate to each other. The README demonstrates this with a minimal example: a schema with a single "hello" field that returns the string "world." Once the schema is defined, the library handles parsing incoming GraphQL queries, validating them against the schema (catching errors like requesting a field that does not exist), and executing them by calling "resolver" functions that retrieve or compute the actual data. GraphQL.js is a general-purpose library that works both in Node.js server environments and in the browser. Higher-level GraphQL server frameworks (like Apollo Server) are built on top of it. You would interact with GraphQL.js directly when building a custom GraphQL server or when you need low-level control; most application developers use it indirectly through a higher-level framework. It is distributed as an npm package and is written in TypeScript.

Copy-paste prompts

Prompt 1
Show me how to define a simple GraphQL schema with a few fields and set up resolvers to return data when those fields are queried.
Prompt 2
How do I parse and validate a GraphQL query string against my schema, then execute it to get results?
Prompt 3
What's the difference between using GraphQL.js directly versus using a framework like Apollo Server on top of it?
Prompt 4
Help me build a minimal GraphQL server in Node.js using this library that accepts queries and returns JSON responses.
Prompt 5
How do I handle errors in GraphQL.js when a query requests a field that doesn't exist in my schema?
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Generated 2026-05-18 · Model: sonnet-4-6 · Verify against the repo before relying on details.