Quoting Mitchell Hashimoto
Simon Willison · Simon Willison · 2026-05-14
Mitchell Hashimoto observes that Bun's rapid rewrite from Zig to Rust—accomplished in roughly one to two weeks—demonstrates that AI tooling has made programming languages fungible, no longer a source of meaningful technical lock-in.
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Extraction
Topics: programming-language-lock-inai-assisted-programmingbunrustzig
Claims
- Bun rewrote its codebase from Zig to Rust in approximately one to two weeks.
- This speed demonstrates that with modern AI tooling, any programming language is now expendable once it stops being optimal.
- Programming language selection is no longer a significant lock-in decision because the switching cost has effectively collapsed.
Key quotes
Programming languages used to be LOCK IN, and they're increasingly not so. You think the Bun rewrite in Rust is good for Rust? Bun has shown they can be in probably any language they want in roughly a week or two. Rust is expendable. Its useful until its not then it can be thrown out. That's interesting!