a different guest
You asked for a different domain.
So you got a different file. Same process, same port, same container — the hostname is the only thing that changed.
independence
Nothing is shared but the renderer
Change this file and only this domain changes. There is no shared theme to break, no build to rerun, no cache to clear — the next request reads the file again.
Add a third domain and you add a third file. That is the whole scaling story.
