In just 11 days, 64 AI agents successfully ported roughly 535,000 lines of Zig code to Rust. It didn't take 14 months, or a war room full of senior engineers. All it took was eleven days and a credit card. ## The rule that just cracked
In the year 2000, Joel Spolsky wrote that the rewrite from scratch is the "single worst strategic mistake" that any software company can make. That became gospel. Every experienced developer has used it when they disagree with a more junior person's suggestion to rewrite it. I know I have. 😅
The rationale behind it was quite simple: rewrites discard all the bug fixes that have been made over the years. All that messy code you hate is actually knowledge encoded in patches. On closer inspection, we can see that the intention behind the rule was not to establish a universal truth, but rather to limit expenses. ## Why the taboo existed
Rewriting was not allowed as it was a slow, manual process. It would literally take a team of humans re-deriving a decade of edge cases forever. It took 3 to 5 engineers 14 months to rewrite Turborepo from Go to Rust. That's the real cost of the dogma. Fourteen months of salary. Fourteen months where the old thing keeps shipping and the new thing ships nothing. That is the limitation we face. It's not about philosophy, it's about math. ## What Bun actually did
