π¨βπ Turn API specifications into production-ready SDKs, validators, mocks, and more. 20+ plugins. Millions of weekly npm downloads. Used by Vercel, OpenCode, PayPal, AWS, Autodesk, and many more.
npm install hey-api
Hey API
"OpenAPI codegen that just works."
β Guillermo Rauch, CEO of Vercel
Manual Β β’Β Issues Β β’Β Contribute
About
Hey API is an ecosystem for turning API specifications into production-ready code. It's trusted by thousands of companies β from YC startups to Fortune 500 enterprises β and powers products used by millions worldwide.
This is the monorepo containing all open source Hey API packages. For package-specific documentation and quick start guides, see the individual repositories below.
Packages
| Package | Description |
|---|---|
openapi-ts
|
TypeScript code generator with 20+ plugins for SDKs, Zod schemas, TanStack Query hooks, and more.
Manual Β β’Β npm |
openapi-python
|
Python code generator for SDKs and Pydantic models.
Manual Β β’Β npm |
Highlights
- production-grade code that compiles
- runs in any Node.js 22+ environment
- accepts any OpenAPI specification
- core plugins for SDKs
- HTTP clients for Fetch API, Axios, Angular, Next.js, Nuxt, HTTPX, and more
- Zod schemas, TanStack Query hooks, Pydantic models, and 20+ plugins to reduce third-party boilerplate
- highly customizable via plugins
Libraries
| Package | Description |
|---|---|
spec-types
|
TypeScript definitions for OpenAPI and JSON Schema specifications with complete inline documentation.
npm |
Contributing
Want to see your code in products used by millions?
Start with our Contributing guide and release your first feature.
Sponsors
Partners behind the future of API tooling. Become a sponsor.
Gold
|
|
Silver
scalar.com |
fastapi.tiangolo.com |
getunblocked.com |
Bronze
|
|
License
Released under the MIT License.