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# Bug [Next.js 16]: Vercel console warning about middleware missing

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Lesley (@ldeveber) · 2025-10-25

Hi! I recently upgraded to Next.js 16, and I’ve already run the codemod to migrate `middleware.ts` to `proxy.ts` as described here: https://nextjs.org/docs/messages/middleware-to-proxy

However, I’m getting the following warning when deploying:

> WARNING: Unable to find source file for page middleware with extensions: tsx, ts, jsx, js, this can cause functions config from `vercel.json` to not be applied

I’m assuming this is a minor display thing and not actually an issue but wanted to confirm anyways. Thanks in advance!


Ahmetkaya (@ahmetkaya) · 2025-10-25

I have the same problem and haven't found a solution yet.


Siam Ahnaf (@siamahnaf198) · 2025-10-25

I also facing same issues. What you meaning about this reply?


Jacob Paris (@jacobparis) · 2025-10-25

You can safely ignore this warning, it's a false positive for some code looking for a middleware.ts file and not recognizing proxy.ts as a valid alternative

There is an active PR to fix this

https://github.com/vercel/vercel/pull/14140


Swarnava Sengupta (@swarnava) · 2025-10-30

Thank you so much for your patience while we worked on this. We wanted to let you know that we have just published a new version of the Vercel CLI on our build infrastructure. With this update, you should no longer see warnings about legacy **`middleware.ts`** when using Proxy files on Next.js v16+.

Please feel free to test it out, and let us know if you encounter any further issues. We're here to help!