@ericbuijs Hi Eric, just came across your post via HN. I wanted to point out another example of ActivityPub in the wild: LearnAwesome.org is an open-source equivalent of GoodReads (but covers all media formats, not just books). I recently added ActivityPub support so you can follow any of their user's book reviews right here in Mastodon: https://github.com/learn-awesome/learn/issues/121
It was quite fun to implement in Rails, actually. I'm very optimistic about open-source webapps adopting it as a general pub/sub.
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