Instead of relying on an external service, which may go down if the maintainers get bored, I think this would be a part of lemmy itself. As in, every instance would maintain an index of all of the other instances it knows about. I'm thinking the process would look something like this:
- Your instance broadcasts that is open for federation
- Another instance either approves federation by broadcasting its own message
- Instances go out and update their index regularly (daily or weekly) with instances they're federated with
This wouldn't require a ton of storage because all it really needs is community name, basic stats, and maybe a short blurb.
check out some instance's local communities
Yeah, I agree. There's a bug for switching your default instance, and perhaps it could be implemented as an anonymous "account" where you could switch between them at will. Basically, you'd "login" without a username, and you'd just have certain features disabled, like voting and commenting.