SPA rewrites return 404 on custom domain (memeduck.in) but 200 on .vercel.app

Hi Vercel Community & Team,

Project: memeduck (Hobby plan) Custom Domain: www.memeduck.in / memeduck.in

Issue: Dynamic Single Page Application (SPA) rewrites configured in vercel.json (/post/[id], /profile/[username]) work properly with HTTP 200 on the raw deployment URL.

However, the exact same routes return a Vercel Edge 404 NOT_FOUND when accessed via our custom domain (https://www.memeduck.in/post/123) or assigned domain alias (memeduck-five.vercel.app).

www.memeduck.in

MemeDuck - Share & Discover Memes

MemeDuck is a social platform to create, share, and discover the funniest memes.

Configuration Details:

The domain shows "Valid Configuration" with blue checkmarks in the dashboard.
Domain is assigned to the active Production branch (main).
We have already verified the rewrite rules and tried removing/re-adding the custom domain, but the edge nodes continue serving 404s for dynamic routes on the custom domain while serving 200s on the raw deployment hash.

Could someone please help check why edge routing fails for rewrites on custom domains?

Thank you!

There's another community post with 404 debugging tips that might be helpful. Please give these solutions a try and let us know how it goes.

https://community.vercel.com/t/debugging-404-errors/437

Vercel Community

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