Do you have a domain? that needs to be either done by changing nameservers or by adding records

Easiest solution is to use vercel nameservers, and add that domain to vercel i.e. app.site.com

vercel will handle the rest

you can use a permanent redirect like this: https://nextjs.org/docs/app/api-reference/functions/permanentRedirect

permanentRedirect(path, type)

Or you can route inside your domain config, that you want to redirect from site.com to app.site.com

I think @Chalcid wasp meant a multi tenant app
Read through this post: https://vercel.com/guides/nextjs-multi-tenant-application

well, we never know when OP is not answering ^^

Thats true lol

create a A record on dns

Wow the third person that said that 😂

Sorry, guys! Was night time in my time zone

I’m thinking of apps like Tinybird or WorkOS where their site.com is used for landing/marketing. And when you’re signed it, you’re redirected to app.site.com

Yes, I do have a domain

Can you explain further what you need to do

Do you want to redirect users from site.com to app.site.com?

if that, set up a redirect in site.com to app.site.com

and use app.site.com as domain

I'll explain steps in detail if you want

I still want to use site.com for things like /pricing, /about, /contact, for example. However, for paths like /signin, /signup, /slug/dashboard I want them to be at app.site.com

You'll need 2 apps for that

thats a simple way

Ahhhhh. Yes, yes. That does make sense

For the sake of knowledge haha, how would you approach the “difficult” way if you were to do this with one app

For that, You'll have to create a wildcard

for 1 nextjs app

wait not wildcard

You have to create 2 domains, pointing to same app

And in nextjs app only, you'll have to redirect from app.com to app.site.com/signin, it'll be in the same app. However, if you want it such that app.com/signin doesn't work, you might need to use a condition for that, or middlewares.

Also, mark my message as a solution

its not actually difficult, but time-consuming

How would I test this out in localhost?

If at all possible

Let me see

You'll have to run a app twice, each on different port

in .env, set up both the urls, including values for condition

window.location.host, to see the host

here is a example condition(Could be inefficient and could have errors)

const pagesInSubdomain = ["/login"] 
//sign in page
if(pagesInSubdomain.includes(window.location.pathName) && window.location.host !== process.env.SUBDOMAIN_URI)  {
redirect(process.env.SUBDOMAIN_URI + window.location.pathName)
}

it just gives you a idea on how to achieve this

Ahhhh. Okay, okay. Thanks a bunch!!