@f00fc7c8@kind.social A GNU Social account is still able to follow an account on Diaspora the software (D*).

D* accounts cannot follow OStatus accounts and GS followers of a D* account cannot reply to posts, the D* feed is just a news feed.

Here's why:

OStatus is a stack of protocols:

  1. WebFinger
  2. Atom
  3. ActivityStreams v1
  4. WebSub (PubSubHubbub at the time)
  5. Salmon

Diaspora of 2010 did these too, but slightly differently. It defined the WebFinger record differently so the Salmon reply endpoints cannot be found by GS. Also GS does Salmon slightly wrong, so they wouldn't be able to talk anyway.

GS is liberal enough that it can follow any Atom+WebSub feed, if it's AS1 then even better.

Diaspora the protocol is now documented and doesn't mention WebSub, it's Salmon for both replies and for updating followers, so GS without ActivityPub cannot follow e.g. a SocialHome account, as SocialHome was developed from the spec rather than imitating the implementation. D* still keeps the legacy WebSub around and can be followed.

@clacke@libranet.de