Anthropic acquires key AI developer tool startup Stainless, rivals like OpenAI and Google may lose access
Follow UsStainless is known for automating SDK creation and maintenance for APIs across multiple programming languages.
Anthropic plans to gradually shut down Stainless-hosted products after the acquisition.
Existing customers will retain access to previously generated SDKs, but rivals may need alternative infrastructure solutions.
AI company Anthropic has officially acquired Stainless, a startup known for building developer tools widely used across the AI industry, including by rivals such as OpenAI and Google. However, the brand did not officially disclose the financial details, but the reports suggest the deal can exceed $300 million.
SurveyFor the unversed, the startup was founded in 2022 by former Stripe engineer Alex Rattray and it became popular simplifying the process of building and maintaining software development kits (SDKs). These SDKs help developers connect applications with APIs across multiple programming languages such as Python, Go, Java, Kotlin and TypeScript.
The startup gained traction among AI companies because its tools could automatically generate and update SDKs whenever APIs changed, reducing the need for manual maintenance. The technology became especially useful for firms developing AI agents and connected services that rely on external software integrations.
Anthropic confirmed that Stainless had already been powering the company’s official SDKs for several years. However, after the acquisition, the company plans to gradually shut down Stainless-hosted products, including its SDK generation platforms.
Even after the shutdown plans, Anthropic said existing customers would retain ownership of SDKs they had already generated and would continue to have the ability to modify and expand them. Interestingly, Stainless tools had previously been used by several major AI firms and cloud platforms beyond Anthropic.
Now that the startup is joining Anthropic, competing companies may need to seek alternative infrastructure solutions for SDK management and API integrations. In a statement shared alongside the announcement, Rattray said the decision to join Anthropic felt natural given the close collaboration between the two companies over the years. He added that the Stainless team would continue focusing on developer infrastructure while contributing directly to Anthropic’s growing AI platform efforts.
