Bun ditches Zig for Rust with help from Claude Fable 5, writes over a million lines of code in 11 days

The JavaScript runtime Bun has completed a migration of its codebase from the Zig programming language to Rust. The transition involved rewriting over one million lines of code in 11 days with the assistance of Anthropic’s Claude Fable 5 model. This overhaul aims to enhance the project's long-term maintainability and performance by leveraging Rust's ecosystem and safety features.