A senior engineer shares how AI agents (Claude) made a previously impractical big-bang migration feasible: migrating hundreds of pages from Bootstrap to Tailwind CSS in 5 days with a 22,000-line PR. The post walks through three experiments — an unguided yolo rewrite that produced a mess, a guided rewrite with clear design system direction that mostly worked, and a cleanup pass that reduced class token count from 33K to 12K. Key insight: AI can handle mechanistic transformations at scale, but humans must define what 'good' looks like first. The author estimates the whole effort cost a few hundred dollars in tokens and would have been economically unjustifiable without AI assistance.
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Managing migrations is the jobSpeed changes the mathAnatomy of a modern big bang migrationWorth it?Liked this article? You’ll love the book100.1K Impressions8 Comments