How Fern runs multi-tenant docs for Webflow and ElevenLabs on Vercel

In three linesFern, a developer documentation platform hosting docs for Webflow and ElevenLabs on Vercel, migrated 65% of its app from Pages Router to App Router in 7 days. Results: 3x faster TTFB, 80% reduction in page load times, 6M+ monthly page views, deployments in 5 minutes.

Summary generated by Claude — human-verified