Anthropic announced Monday that it has acquired Stainless, a startup founded by former Stripe engineer Alex Rattray. The company’s software is widely used by rival AI labs such as OpenAI and Google.
Anthropic did not disclose terms of the deal. However, The Information reported last week that the company is in talks to buy Stainless, which is backed by Sequoia Capital and Andreessen Horowitz, for more than $300 million.
The acquisition will take a major infrastructure supplier out of the hands of Anthropic’s competitors. The company told TechCrunch that it is scaling back all hosted Stainless products, including SDK generators. An Anthropic spokesperson said Stainless customers will continue to own the SDKs they have generated to date and have full rights to modify and extend them as they wish.
Founded in 2022, the New York-based startup has made a name for itself in the emerging AI industry by automating the creation and maintenance of software development kits (SDKs), the libraries that developers use to interact with APIs.
Rattray has developed software that can take API specifications and transform them into production-ready SDKs across multiple programming languages, including Python, TypeScript, Kotlin, Go, and Java. This tool has become popular because the platform automatically updates the SDK in response to API changes, eliminating the need for the time-consuming process of manual maintenance.
This technology is especially valuable to companies like Anthropic, OpenAI, Google, Replicate, Runway, and Cloudflare that are building AI agents that can connect to external software to complete tasks on your behalf. The Stainless SDK tool is an easy way to build and maintain these connections, but going forward, this tool will only be available to Anthropic and not to our competitors.
According to Anthropic, Stainless software has helped generate all official Anthropic SDKs since the early days of the API.
“I started Stainless because an SDK requires as much care as the API it wraps,” Rattray said in a press release posted Monday. “Anthropic was one of the first teams to bet on this with us. We’ve been watching what developers have been building on Claude for the past few years, so it was an easy decision to bring the team together. It allows the team to continue doing the work we love on the platform that matters most.”
If you buy through links in our articles, we may earn a small commission. This does not affect editorial independence.
