On December 3, 2025, Anthropic announced that it had reached an agreement to acquire the JavaScript runtime Bun, while disclosing that its intelligent coding product, Claude Code, had surpassed $1 billion in annualized recurring revenue approximately six months after it was made available to the public. Anthropic said the acquisition aims to further improve Claude Code's performance and stability, as well as accelerate product iterations for enterprises and developers.
Founded in 2021 by Jarred Sumner, Bun combines a runtime, package manager, packaging tool, and testing framework with a focus on high-performance and all-in-one development experiences, with millions of downloads per month and has been used by technology companies to speed up the development process. Anthropic noted that Bun has long played a key role in Claude Code's infrastructure, and will continue to be open source and licensed with MIT after this merge, and its core capabilities for JavaScript and TypeScript developers will continue to be invested.
Anthropic also emphasized that it will integrate more closely with Claude Code while maintaining Bun's unique technical route to support enterprise customers including Netflix, Spotify, KPMG, L'Oréal, and Salesforce to expand AI-assisted development scenarios. The company said that such targeted acquisitions will focus on the layout of technology base and enterprise-level AI capabilities, and will continue to cautiously pursue similar transactions in the future.
FAQ
Q: What is the core content of Anthropic's announcement?
A: One is the acquisition of JavaScript runtime Bun, and the other is the disclosure that Claude Code's annualized recurring revenue has exceeded $1 billion.
Q: What is Bun and what will change in the future?
A: Bun is an all-in-one JavaScript runtime and toolchain that will remain open source and licensed under MIT after being incorporated into Anthropic, and will continue to provide performance optimizations to all developers.
Q: What is the current stage of development of Claude Code?
A: Claude Code has been generally available since May 2025, achieving $1 billion in annualized revenue in just about half a year, and has been adopted by several large enterprises.
Q: What is the direct impact of this acquisition on developers?
A: It is expected to bring faster code generation and execution performance, a more stable infrastructure, and a tighter, integrated development experience in JavaScript/TypeScript scenarios.
Q: Will Bun only serve Anthropic's own products after the merger?
A: The official statement is that Bun will continue to be an independent open source project for all developers, while providing more in-depth support for Claude Code.