How Fern delivers 6M+ monthly views and 80% faster docs with Vercel
By Steven Van ·
Fern serves API docs for Webflow and ElevenLabs from one Next.js app on Vercel, with deploys 83% faster and TTFB 3x quicker.
Fern, a documentation platform used by companies including Webflow and ElevenLabs, serves more than 6 million page views and 1 million unique visitors a month from a single Next.js application running on Vercel, according to a case study published by Vercel.
Instead of deploying a separate instance per customer, Fern routes traffic across customer domains from one codebase using Vercel Middleware. Its deployment setup spans three environments: a main multi-tenant stack at prod.ferndocs.com, a CDN-focused version at app.ferndocs.com, and a dev environment at dev.ferndocs.com. Customers can bring their own subdomains (docs.website.com) or subpaths (website.com/docs) by adding a single CNAME record.
- Migrating to Next.js App Router cut page load times by 50-80%, improving navigation speed and Lighthouse scores.
- Moving off AWS Fargate reduced deploy times by 83%.
- Time to first byte is now 3x faster.