Engineer Rebuilds Next.js From Scratch in a Week Using Claude AI

A Cloudflare engineer just speed-ran one of web development's most ambitious solo projects: rebuilding Next.js from the ground up in a single week, powered almost entirely by Anthropic's Claude AI.

The result? A reimplementation covering 94% of the Next.js API. The bill? $1,100 in Claude tokens. The tool swaps out Next.js internals for Vite, effectively sidestepping the Vercel lock-in that's long been a sore point for developers deploying elsewhere.

The project is a striking proof of concept for AI-assisted development at scale. Rather than writing the framework line by line, the engineer directed Claude through the massive reimplementation — treating the LLM as a turbocharged coding partner.

It also signals growing tension in the framework ecosystem. Cloudflare clearly wants Next.js compatibility without the Vercel dependency. AI just made that dramatically faster to achieve.