app/sitemap.ts is not served at /sitemap.xml on NextJS 15RC about next.js HOT 4 CLOSED

It's an expected breaking change as the PR description mentioned, that we don't appending .xml extension for the dynamic sitemap.ts routes anymore.
If you're using sitemap.xml static file convention, it stills works as /sitemap.xml, but if you're using any dynamic routes with .ts or .js extension, the url is now /sitemap , and will be /sitemap/[id] if you're generating multi sitemaps with generateSitemaps() API.

We mentioned in the blog post but didn't mention it as breaking change, I've updated the blog post that it's mentioned as below now

[Breaking] Remove .xml extension for dynamic sitemap routes and align sitemap URLs between development and production (PR)

from next.js.

It's an expected breaking change as the PR description mentioned, that we don't appending .xml extension for the dynamic sitemap.ts routes anymore. If you're using sitemap.xml static file convention, it stills works as /sitemap.xml, but if you're using any dynamic routes with .ts or .js extension, the url is now /sitemap , and will be /sitemap/[id] if you're generating multi sitemaps with generateSitemaps() API.

We mentioned in the blog post but didn't mention it as breaking change, I've updated the blog post that it's mentioned as below now

[Breaking] Remove .xml extension for dynamic sitemap routes and align sitemap URLs between development and production (PR)

Thanks for the explanation. So there is no NextJS recommended way to serve the dynamic sitemap at /sitemap.xml, do I get this right? Because to me that sounds like a downside.

from next.js.

As a solution you can add rewrites to next.config.js

async rewrites() {
    return [
      {
        source: "/sitemap.xml",
        destination: "/sitemap",
      },
    ];
}

from next.js.

I had a PR (#66477) to improve the sitemap url generation, where we can always get a .xml for both single route and dynamic routes. This will resolve the migration pain

from next.js.