Just found out about this and thought it was neat. For those of you that don't know, a Lemmy instance won't automatically federate everything everywhere all at once. It'll federate only what local users are subscribed to. So someone made a tool that will let you increase visibility of smaller communities that might not be synced to every instance.

Looks like it's opt-in, and instances can avoid using it. Some do because it's a lot of server cost for stuff they don't care about.

I've created a few communities, and wondered why I was immediately getting ~30 subscribers, and this is probably why