Bun rewrites from Zig to Rust with Claude Fable 5 AI assistance in 11 days

The JavaScript runtime Bun has fully migrated from Zig to Rust, completing a full code rewrite.

Published 3j1 sourceNotable

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The fact

Anthropic's Claude Fable 5 AI generated over a million lines of code to facilitate this transition.

The project was completed in 11 days, showcasing AI-driven acceleration in technical overhauls.

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