Jared Sumner rewrote Bun's entire codebase from Zig to Rust by running 64 parallel Claude (Fable pre-release) instances across four work trees, porting and validating files against the existing test suite.

13:42talks about how he used basically parallel clouds to rewrite this the zig codebase in rust and uh this visual shows he basically had four work trees and 64 instances of claude using fable like like the pre-release version >> all rewriting the basically porting the files from zig to rust checking make to make sure the test pass but this is a good case study of like using AI for

14:10this type of thing at scale. Um I mean even the idea of running 64 cloud instances like not everybody can do that. Like this is a very particular type of development work where you're taking an existing codebase with an existing test suite and basically just making sure that the rewrite passes those tests. >> Yes. >> Um not every software project can throw 64 instances of claude at it to just

14:34like move faster. >> No. Oh, and I believe this cost like $140,000 worth of tokens. >> I think like I read 100,000 in that range like over 100,000. But in the blog post he mentions that this without Claude would have taken a team of four like a year. >> Yes. >> So if you compare that cost, >> then you know it's potentially worth it. But I I will back up a second and say

15:00that this this whole thing is also just an ad for Claude and Anthropic and AI. Like it's it's it's like sure it's a cool technical feat overall, but we we can't forget the fact that Anthropic now owns Bun and it's good news for them that a a project like this was capable and and like to be able to go to the CEO of some other company who's not super

15:23technical and be like, "Oh, you should be running 64 instances of Claude. That's going to make anthropic more money. $165,000. You found it. Yeah. >> Yes. $165,000 of tokens to do this rewrite. Yeah. 690 million output tokens, man. >> Insane. >> That's crazy. That's >> absolutely insane. >> Absolutely insane. Well, either way, this blog post came out and then here we have Andrew Kelly who then wrote his