Fern provides SDK generation tools that automatically create language-native client libraries from API specifications like OpenAPI or AsyncAPI. This platform ensures strong typing, inlined documentation, and idiomatic code across supported languages such as TypeScript, Python, and Go. By automating this process, Fern allows engineering teams to focus on API development while maintaining high-quality, synchronized developer resources.
Funding
$13.3M raised to dateRaised to date based on public sources. This may differ from the amount the company actually raised and is based only on what is publicly available on the internet.
NIFounders
Product
Problem
Developing and maintaining API client libraries (SDKs) and documentation across multiple programming languages is a time-consuming and error-prone process. Manually creating these resources diverts engineering effort from core feature development and can lead to inconsistencies between the API and its documentation.
Solution
Fern automates the generation of type-safe SDKs and comprehensive API documentation directly from OpenAPI specifications or its own API definition format. By importing an API definition, Fern produces idiomatic client libraries in languages like TypeScript, Python, Java, Go, Ruby, C#, and PHP, along with a customizable API documentation website. This process ensures consistency between the API, SDKs, and documentation, while also reducing the manual effort required for API development and maintenance. The generated SDKs include features like type safety, auto-completion, and retry logic.
Target Audience
The primary target audience includes API developers and platform engineering teams looking to streamline SDK generation and API documentation, particularly those using OpenAPI specifications.
Features
- Generates SDKs in multiple languages (TypeScript, Python, Java, Go, Ruby, C#, PHP) from OpenAPI or Fern definitions.
- Creates a customizable API documentation website with auto-updating SDK code snippets.
- Offers a command-line interface (CLI) for integration into CI/CD pipelines.
- Provides a GitHub app for automated pull requests when the API definition changes.
- Supports custom code additions to enrich generated SDKs with utility functions or wrappers.
- Implements retry mechanisms, such as exponential backoff, for API calls.
- Generates webhook functions for setting up webhook endpoints and validating signatures.