Flex Capital is excited to announce our investment in Fern's $9M Series A.
Every software company today is also an API company — but giving outside developers a world-class experience has always required a dedicated team that only the largest tech companies could afford to staff. Fern changes that, and at Flex we're proud to back the team making great developer experience available to everyone.
Flex Capital is proud to have backed Fern's $9 million Series A led by Bessemer Venture Partners, which brings the company's total funding to $13 million. Founded by Danny Sheridan and Deep Singhvi out of Y Combinator in 2023, Fern is now used by more than 150 companies — including Square, ElevenLabs, Webflow, Cohere, LaunchDarkly, Alchemy, and Intercom.
What Fern Does
- Automated SDKs in every language. Fern uses your API spec to automatically generate and maintain idiomatic SDKs across TypeScript, Python, Go, Java, C#, PHP, and Ruby — publishing straight to GitHub, npm, and PyPI
- Beautiful docs, always in sync. Fern Docs produces highly customizable documentation websites with a built-in API Reference and interactive playground, so SDKs and docs stay consistent from a single pipeline instead of two teams
- Built for the agent era. Fern is extending beyond developer experience to Agent Experience — adding Model Context Protocol support and an "Ask AI" chat trained on your API, so LLMs can navigate and integrate with APIs directly.
Why We Invested in Fern
Building and maintaining SDKs and docs in-house used to take a dedicated engineering team - something only tech giants like Amazon or Palantir could justify, as Fern's founders learned firsthand at those companies. Fern collapses that work into a 2-in-1 solution that is fully automated, always in sync, and powered entirely by a customer's existing API specs.
We're proud to back Danny, Deep, and the Fern team as they build the connective tissue between the world's APIs and the developers - and agents - who depend on them.
