fern-api/fern
Input OpenAPI. Output SDKs and Docs. observed · 2026-08-28
Health v2 · maintenance only
89/100
- Activity 99
- Release rhythm 71
- Longevity 100
How is this computed?
round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10) — computed 2026-09-03. Adoption (stars, forks) is never an input.
- gap_med: 0.0
- age_days: 1615
- days_rel: 113
- days_push: 7
- n_releases_24m: 1277
Adoption not part of the score
3764 stars · 339 forks observed · 2026-08-28
What it is AI-extracted, prompt v1, taxonomy v1, 2026-08-29, confidence not recorded
Fern is a CLI-based platform that takes OpenAPI (and AsyncAPI, Protobuf, OpenRPC) definitions and generates type-safe SDKs in multiple languages plus developer documentation with API references. It is distributed as an npm package and runs on Node 18+.
Use cases
- generate sdks from openapi spec
- generate api documentation from openapi
- create typescript and python client libraries for my api
- keep sdk and docs in sync with api definition
- generate multi-language sdks for rest api
- build developer docs with api reference
- docs as code pipeline for api
When to choose
- you maintain a public or internal API and want to ship SDKs in several languages
- you want documentation and SDKs generated from a single API definition
- you use OpenAPI, AsyncAPI, Protobuf, or OpenRPC specs
- you want docs-as-code with CI-friendly generation
When to avoid
- you don't have a machine-readable API definition
- you need fully hand-crafted SDKs with custom idioms beyond what generators produce
- you only need a static site generator unrelated to APIs
Facets
cli-tool · maturity active
sdk documentation api-documentation cli developer-tools apis web-development documentation cli cross-platform sdk-generator openapi docs-as-code api-reference multi-language-sdks code-generation nodejs
2 sources
- readme: https://github.com/fern-api/fern · fetched 2026-08-28 · f8403a52e357
- homepage: https://buildwithfern.com · fetched 2026-08-29 · 44136fa355b3
Member repositories
| Repository | Role | Health v2 |
|---|---|---|
| fern-api/fern | main | 89 |
For agents
Data as of 2026-08-30T08:39:29.467469+00:00 · Report a problem