Ghost is a lot like substack, but instead of, say, someone like Ken Klippenstein owning their own domain name and redirecting it to substack content, Ken Klippenstein could have his own domain and host his own substack-like-Ghost on that domain. Because it’s federated, it could directly interact with other Ghost instances potentially as well as Lemmy, Mastodon, and so forth.

(I think it’s a little silly that one of their example images shows it federating with Bluesky when Bluesky has its own proprietary protocol.)

It’s because like all the rest of the federated web, it uses ActivityPub, and thus can interface with other services using ActivityPub. The instance and usernaming scheme works very similarly as here on Lemmy, actually, based on their documentation.

I do think it’s a little sad that it’s only available to people on the Pro tier, which means you have to pay for access to this feature currently through paying for hosting directly from Ghost themselves. While Ghost does need a pathway to self-sufficiency, hopefully this will be removed in the future, because it is a bit antithetical to actually hosting your own instance, by forcing you to use their hosting services.