You shouldn’t need to set NITRO_PRESET or the output directory - you can leave that blank. Have you configured anything else, such as a custom vercel.json or configuration in your Nuxt config file?

Finally, given what you want, do you want a static generated site (nuxt generate) or an SSR/hybrid app (nuxt build)?

Hello Daniel*, and thanks for your reply!

I don’t have a vercel.json, and there’s nothing specific to Vercel in my nuxt.config.ts.
I removed the NITRO_PRESET environment variable and tried a new deploy, but the issue persists.

I want SSR because my pages are dynamically generated from a database and cannot be static.

Everything works as excepted with Netlify, but I can’t understand why the time to first byte is so long (example: https://osso.labandotheque.fr), so I wanted to give Vercel a try.

osso.labandotheque.fr

Osso | (Oscillateurs Sonneurs) Bal neo-trad BZH · La Bandothèque

Le duo OSSO (Oscillateurs Sonneurs) est un projet expérimental pour la danse (fest-noz & bal folk) où les frères Le Breton, s’inspirant de la tradition des sonneurs de couple, remplacent les instruments acoustiques par des synthétiseurs, et utilisent les codes de la musique électronique pour produire des sonorités enveloppantes avec un jeu en temps réel à quatre mains.

Do you need more details about my config?

Thanks for your help!

* I didn’t expect you to respond directly, but I just wanted to take the opportunity to say that I’m a big fan of your work :)

How strange. Do you have a public repo? Can you reproduce minimally? I’d happily take a look.

And thanks for the kind words 😊

I finally found the reason, It was because of this in my nuxt.config.ts:

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nitro: {
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    routeRules: {
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      "/**": {
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        headers: {}, // <-- this object should not be empty for Vercel
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      }
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    }
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  }

I can't remember why, but put an empty {} in headers was necessary to enable something in Nitro, like a {} in .prettierc to enable formatting.

So I just added a property in the headers object, and now it's working.

Since it’s not an issue on Netlify but it is on Vercel, maybe we should report it to Vercel or handle this specific Nuxt warning when deploying there?