Significant TTFB delay on Cloudflare Worker vs Vercel using same OpenNext setup
I'm using OpenNext to deploy a Next.js 15.3 site with ISR and streaming enabled.
When deployed to:
Vercel: the initial document load (document in Network tab) is ~389ms
Cloudflare Workers: same route takes ~6.3s for the initial document response
Both environments use the exact same codebase, and both are rendering an ISR page (non-cached). The rest of the assets load quickly in both cases. Only the HTML response (document) is delayed on Cloudflare.
When deployed to:
Vercel: the initial document load (document in Network tab) is ~389ms
Cloudflare Workers: same route takes ~6.3s for the initial document response
Both environments use the exact same codebase, and both are rendering an ISR page (non-cached). The rest of the assets load quickly in both cases. Only the HTML response (document) is delayed on Cloudflare.


