Bun Acquired by Anthropic to Bolster AI Coding Infrastructure

Bun, the high-performance JavaScript runtime, bundler, and package manager, has been acquired by artificial intelligence firm Anthropic. The acquisition is set to accelerate the development of Anthropic’s successful agentic coding platform, Claude Code, which recently achieved a reported $1 billion run rate and already utilizes Bun as its bundled runtime. Anthropic’s rationale for the acquisition centers on integrating Bun’s technical excellence to redefine speed and performance for modern software engineering within its enterprise AI offerings. Bun’s founder, Jared, and his team will continue to focus on high-performance JS tooling and Node.js compatibility, with a core commitment to keeping Bun open source under the MIT license.

From Bun’s perspective, the acquisition addresses critical long-term sustainability concerns, providing dedicated resources and stability. Despite raising $26 million in venture capital, Bun had not generated revenue, posing challenges for its future and team monetization. This move allows Jared to concentrate on product development rather than company management or investor relations. While the community reactions range from skepticism regarding Bun’s open-source future to speculation about Anthropic entering the cloud provider space, Anthropic has explicitly stated Bun will remain open source. This strategy contrasts with approaches by other major AI labs that have opted for costly rewrites in languages like Rust for performance, highlighting Anthropic’s intent to invest in and leverage the existing JavaScript ecosystem for its AI coding tools, particularly for concurrent, LLM-driven workloads.