ActivityPub and Interoperation
ActivityPub is supposed to allow content from one users activity feed to show up in another
I can see roughly what this means for Mastodon instances. You toot and then you push those toots to other servers.
It's easy to imagine when we're dealing with the same applications. But what about different applications? What about Mastodon and Lemmy (a Reddit clone)?
A good article about it is here:
https://vijayprema.com/using-lemmy-from-my-existing-mastodon/
Basically you can
- Post to Lemmy by posting to Mastodon and @ mention the group you want to post to. First line becomes the title of the post
- Reply to a Lemmy post: Get the direct link to the Lemmy post/comment using its "rainbow Fediverse" link button in Lemmy, paste it into your logged in Mastodon instance search bar, and then press Reply and post your reply.
BookWyrm
See here:
https://docs.joinbookwyrm.com/activitypub.html
According to some sources, you can follow Bookwyrm users from your Mastodon instance and you'll see their updates in your feed. This appears to be because BookWyrm convert their custom object types into standard ones when send updates to non-bookwyrm instances.
Shows how Bookwyrm maps to ActivityPub: https://docs.joinbookwyrm.com/activitypub.html
Bookwyrn uses special Object types that get converted to standard ones when they go out.
Mastodon
Describes how Mastodon concepts map onto ActivityPub concepts: https://docs.joinmastodon.org/spec/activitypub/