A community to talk about the Fediverse and all it's related services using ActivityPub (Mastodon, Lemmy, KBin, etc).
If you wanted to get help with moderating your own community then head over to !moderators@lemmy.world!
Learn more at these websites: Join The Fediverse Wiki, Fediverse.info, Wikipedia Page, The Federation Info (Stats), FediDB (Stats), Sub Rehab (Reddit Migration), Search Lemmy
You just described (my service, paid hosting) Communick.
Sign up at the main "portal", choose your plan and your username will be the same on all services that you activate. You get your mastodon account as @your.username@communick.com, your Matrix id is @yourusername:communick.com, and your Lemmy account is @your.username@communick.news. Authentication is unified - except for Lemmy, which does not provide an easy way for SSO.
As pretty as that would be it has its problems. For this to work you need an authentication service. If you use that service for everything then your accounts are linked to this auth provider and you get a problem if that service goes down. You create a single point of failure.
That being said matrix and mastodon support oauth providers. So it is possible to have unified authentication provider for these two. Lemmy doesn't support this yet.
You can make it just be a private key, where you sign a message with it to log in. The service just needs to know your public key
The problem is not the data. Only the central nature and the dependency on a central point.
You should only need one key to log in everywhere, even if the servers are different
I think at some point the various fediverse components will need to divide up by function, into generic account hosts, generic content hosts, and generic interface hosts. As long as those three functions are bound together, the possibilities for federating between platforms will be limited.
It's being looked into
I think a true unification defeats the purpose of federation. That said, I have been using Lemmy Handshake to sync my subscriptions between accounts. I generally use one account to login, but sometimes an instance has technical issues or content seems to be missing so I like having a backup option in a pinch.
fedilab is kinda close
"User account federation" seems like a cool feature, but fraught with security hurdles.
Activity pub is spose to be email-like.... you wouldn't want a new email account on every server who has users you want to communicate with via email.
Then, would it be a better idea to create one mega-fediverse app that combines but also separates all the different features of each platform (eg: when viewing it on a browser, it would have a Lemmy tab, matrix tab, mastodon tab, etc) and then have the functionality and format be separate for each one of those instead of trying to pull a "can do everything, good at nothing" type of platform? That would solve the email issue, but I feel it would be more complicated to implement but I've also never developed anything remotely like that ever and so I'm not qualified to speak on it.
Honestly, I feel like the answer you're looking for is a federated single sign on app. The real challenge will be building the right tools and community mindset for determining what a "trusted" instance is.
i agree there is an auto-federated SSO opportunity here, but it be dangerous.