Anthropic Acquires Dev Tools Startup Stainless, Used by OpenAI, Google, Cloudflare

Anthropic has acquired Stainless, a New York-based developer tools startup used by OpenAI, Google, and Cloudflare, according to a May 18, 2026, report by TechCrunch AI. The acquisition will see Stainless wind down its hosted products, marking a shift in the AI development tools landscape.

Founded to provide infrastructure for AI model development, Stainless had counted three of the industry’s largest players among its clients. The startup’s tools enabled companies to manage complex workflows in AI training and deployment. As reported by TechCrunch, the acquisition aligns with Anthropic’s strategy to strengthen its position in foundational AI infrastructure.

The move underscores growing consolidation in the AI development tools sector. A Google News summary of the acquisition noted it represents “a strategic expansion in AI development infrastructure” as major players seek to control more aspects of the AI stack. With all companies involved based in the United States, the acquisition has implications for domestic AI development practices.

Terms of the deal were not disclosed. Stainless’s existing products will be phased out as Anthropic integrates the startup’s technology and talent into its operations.