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.
5,383
stars
7,233
commits
TypeScript
primary language
Aug 24, 2026
updated
README
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
Bronze
|
|
License
Released under the MIT License.
Contributors
(top 30 of 182)
2,453 commits
1,188 commits
669 commits
669 commits
Similar repos
Languages
TypeScript
95.4%
Python
2.5%
MDX
1.2%
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.
5,383
stars
7,233
commits
TypeScript
primary language
Aug 24, 2026
updated
README
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
Bronze
|
|
|
License
Released under the MIT License.
Similar repos
Contributors
(top 30 of 182)
2,453 commits
1,188 commits
669 commits
669 commits
Languages
TypeScript
95.4%
Python
2.5%
MDX
1.2%