Writing out (what I hope will be) a comprehensive overview of techniques that ActivityPub node operators can use to prevent spam.

While I've yet to encounter spam on the Fediverse, it seems inevitable that this will happen without intervention.

If we can create some good techniques to address spam before it happens, maybe we can stop spam from ever being a problem on the Fediverse.

Thanks @cwebber for helping co-author, as well as originating many of the ideas! Really excited to work on it!