Allow delegation of a Lemmy instance to a different URL?

Is it possible, or will it be possible eventually, to delegate your Lemmy instance to a different URL?

For example, if I wanted to setup my own self-hosted instance at example.com, so that my username would be @greg@example.com, would it then be possible to host the actual Lemmy installation at example.com/lemmy/, leaving the main domain example.com available for me to host whatever I want?

I would love to setup my own instance with a nice short domain, instead of something like @greg@lemmy.example.com, but without being able to delegate you essentially have to sacrifice the whole domain to the Lemmy installation, which is something I don't really want to do with a short domain.

What came to mind is OpenID, where using the example above, you could use example.com to sign-in to any site that supported OpenID, and then on example.com you would have a link to the actual OpenID provider in the code somewhere, and everything just worked.