Robin Berjon: Running ActivityPub over ATProto

Robin Berjon posted about an interesting thought experiment, referencing his latest blog post:

With some disclaimers:

This is just a sketch and it has issues. I initially wanted to prototype this but the situation at work is such that I have precious little bandwidth for prototyping (so I’m mostly dumping my notes onto this blog). Think of it as a design provocation, and the provocation is this:

With relatively little work, we could run ActivityPub atop an AT Protocol PDS.

I won’t try to convince you that we could do that without making some modifications to the current state of either or both, but I would like to draw your attention to why this is something worth thinking about and, with any luck, convince you that we should be moving in that direction (even if not necessarily this exact combo).

And, though more people probably mused with the thought, Berjon may be the first to put it into words.

Open invitation to anyone to brainstorm some more on this thought train…


This is an interesting idea. I’m not familiar enough with the AT Proto spec to comment on what would make this easy or difficult, but I’d like to see someone get into the weeds on this.

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