ActivityPub over ATProto
This post provocatively suggests integrating ActivityPub with the AT Protocol, aiming to combine the strengths of both federated social media standards. It delves into the architectural details of how AP's actor documents could leverage ATProto's Personal Data Servers for improved user agency and credible exit. The idea offers a novel perspective on a frequently debated topic within the open social media space, challenging the common 'either/or' mentality.
The Lowdown
Robin Berjon's article, 'ActivityPub Over ATProto,' posits a compelling architectural thought experiment: integrating ActivityPub with the AT Protocol. Amidst the 'factions' of open social media, the author proposes a hybrid approach, arguing that these two distinct protocols, often seen as rivals, actually solve complementary problems and could achieve a more robust federated ecosystem when combined. This is presented as a 'design provocation' rather than a fully implemented solution.
- The Core Idea: The central proposal is to run ActivityPub atop an AT Protocol Personal Data Server (PDS) with relatively minor modifications.
- ATProto's Strengths: ATProto is highlighted as a generic toolbox for social apps, offering pluggable identity, signed data repositories, and 'credible exit,' which ensures user control and content portability independent of server hosts. It acts as a user-centric Personal Data Server.
- ActivityPub's Strengths: ActivityPub, based on URLs and ActivityStreams, excels at 'socializing' web content but often leaves users reliant on server administrators.
- Bridging the Gap: The article illustrates how ActivityPub's
Actordocument, which specifies API endpoints, could be reconfigured to point to ATProto PDS endpoints. - Addressing Challenges: Potential issues, such as XRPC's distinction between GET and POST methods and identity system alignment, are acknowledged but deemed surmountable and more 'religious' than technical hurdles.
- Mutual Benefits: Combining the two protocols would leverage ActivityPub's broad federation capabilities with ATProto's strong user agency, potentially creating a more accessible and user-controlled federated social media landscape.
While described as a 'sketch' needing further prototyping, the article serves as a powerful call to move beyond tribalism in the open social media space and explore synergistic solutions that empower users with greater control and freedom.
The Gossip
Protocol Particulars: Practicality and Platform Parallels
The comments quickly dove into the practicalities and perceived differences between setting up ActivityPub and ATProto. One user challenged the ease of setting up an ATProto server integrated with Bluesky, drawing a contrast with ActivityPub's apparent simplicity. Another commenter pushed back, noting the closure of a popular hosting service for ActivityPub instances and arguing that the two protocols have fundamentally different designs and goals, making direct comparisons difficult. A helpful link for setting up an ATProto PDS was also shared.
DWebCamp's Deep Dive
Commenters noted the article's enduring relevance, particularly in light of an upcoming DWebCamp event. This gathering was highlighted as a prime opportunity for cross-pollination and discussion among experts in both ActivityPub and ATProto, suggesting a renewed interest in bridging these protocols. There was also interest in whether event content would be available online for those unable to attend.