Anthropic acquires Bun

The JavaScript tooling project has been acquired by Anthropic, which plans to use it as core infrastructure for its AI coding products like Claude Code and Claude Agent SDK. The project will maintain its open-source, MIT-licensed status, and the existing team will continue active development, focusing on high-performance JavaScript tooling, Node.js compatibility, and replacing Node.js as a default server-side runtime.

This acquisition provides long-term stability and direct insight into the future of AI-driven software development, allowing the tooling to be proactively shaped for that environment. The initial motivation for the project stemmed from frustration with slow iteration times in large codebases, leading to the development of a fast bundler, transpiler, and runtime built around JavaScriptCore for rapid startup. The project evolved into an all-in-one solution that recently gained traction due to its single-file executable format being ideal for distributing AI coding tools. The move allows the project to focus entirely on building the best tooling without the need to seek immediate monetization through a cloud product.