Towards the API platform we always wanted: why we raised our $25M Series A

Stainless has raised $25 million in Series A funding, led by a16z with additional investments from Sequoia, The General Partnership, and new investors like Felicis and MongoDB Ventures, highlighting confidence in its vision to simplify API integration for developers. Since its inception in early 2022, Stainless has aimed to make it effortless for developers to work with APIs by creating an SDK generator that provides high-quality, consistent, and easy-to-use SDKs across multiple programming languages, without the need for companies to dedicate full-time engineers for SDK maintenance. The Stainless SDK generator has been adopted by a wide range of companies, including top AI model providers like OpenAI and fintech businesses, to enhance developer experience (DX) by automating SDK updates and ensuring they are up-to-date and consistent as APIs evolve. This approach helps companies reduce integration efforts and maintain high-quality SDKs that feel handcrafted, addressing the need for robust API tools as APIs become increasingly sophisticated and critical in enabling agentic AI systems. Stainless envisions expanding its platform to become a comprehensive solution for developers working with APIs, aiming to support the growing role of APIs in technology and AI advancements.