GraphQL.js is the official JavaScript reference implementation of GraphQL, the query language for APIs originally created by Facebook. Written in TypeScript, it serves as the canonical implementation that other GraphQL libraries across different programming languages are built against. The repository is hosted at github.com/graphql/graphql-js and provides comprehensive documentation through the GraphQL specification website.
The library provides two core capabilities: building a type schema that maps to application code and serving queries against that schema. Developers can define GraphQL types and fields with resolver functions that return values, promises, or arrays of promises. The graphql function validates queries for syntactic and semantic correctness before execution, reporting any errors encountered. This dual functionality makes it suitable for both server-side API development and client-side applications, as demonstrated by tools like GraphiQL which is built using GraphQL.js.
GraphQL.js is distributed with both CommonJS and ESModule support, enabling seamless integration with modern JavaScript tooling. The library works in Node.js environments and browsers alike, with proper tree-shaking support when bundled with webpack or rollup. The exports map in the package.json directs runtimes and bundlers to appropriate files, while CommonJS code uses .js extensions and ESModule builds use .mjs extensions for tools that don't support the exports field.
The repository's contributor base overlaps significantly with major projects including microsoft/vscode, microsoft/typescript, and rust-lang/rust, indicating its importance in the broader development ecosystem.
The project follows Semantic Versioning and maintains a structured version support policy. The latest major version receives full support including bug fixes and security updates, while the previous major version receives feature support for 12 months after a new major release. Older versions are considered unsupported, though exceptions exist for versions released less than a year prior. Critical security updates are applied to both current and previous major versions, with EOL announcements provided at least six months in advance.
Contributing to GraphQL.js requires signing the GraphQL Specification Membership agreement through EasyCLA, a one-time requirement for individual contributors or their employers. The repository actively welcomes pull requests and maintains detailed release notes and migration guides to assist users upgrading between versions. Community support is available through the GraphQL Discord channel dedicated to graphql-js discussions.
