PORTING 287,000 LINES OF REACT IN 3 DAYS. THE HARD PART WAS PROVING NOTHING CHANGED.

Summary from the TLDR Dev newsletter

Maple moved its observability app from React to Foldkit using about 40 Claude agents, with most human effort going into a harness that compared more than 2,600 screen variants across pixels, structure, network requests, and accessibility. The rewrite took three days, but code review still found about 180 defects the screenshots missed, and the startup bundle roughly doubled.