Wildcard domain and Agent advice

Question

Hello, Im finding an way to automate domain provisioning for clients in my new SAAS.
The agent on railway.com responded to me this way ->
"Your setup:

You have *.app.kilivi-dev.cz pointing to your Railway service
    Your app routes based on subdomain (e.g., client1.app.kilivi-dev.cz, client2.app.kilivi-dev.cz)

What the client does: If they own restaurace-u-draka.cz, they need to create a CNAME record at their DNS provider:

Subdomain: www (or @ for apex)
Type: CNAME
Value: app.kilivi-dev.cz

So www.restaurace-u-draka.cz → points to app.kilivi-dev.cz → which is your wildcard *.app.kilivi-dev.cz

Then in your app: When someone visits www.restaurace-u-draka.cz, the request hits your service. Your app needs to:

Read the Host header
    Identify it's www.restaurace-u-draka.cz (not your domain)
    Route to the correct client's data based on that domain

Important: You'll also need to add restaurace-u-draka.cz as a service domain in Railway so the SSL certificate covers it. But you can do this programmatically if Railway adds API support, or manually for each client.

Does your Payload CMS app already handle multi-tenant routing by domain?"

And I would like to know if its true and I could go by this way and add this approach to the docs for the clients.

0x5b62656e5d · Accepted Answer

If I understand this correctly, you're trying to route users to different domains based off of the client header.

You'd need to set up some kind of function in Railway that intercepts all requests then routes them based on the header value.

Also, you can add domains via Railway's API by using the `customDomainCreate` mutation call.