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Comment by __loam | Hacker News Reader

There's a lot fewer resources for AT than ActivityPub. Last time I checked which was a few months ago, the official documentation for AT was pretty sparse if you're interested in building to a spec. You'll find a lot more in the ActivityPub specs, plus a lot of open implementations and helpful guides.

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> You'll find a lot more in the ActivityPub specs, plus a lot of open implementations and helpful guides.

I've read that there's a problem with interacting with Mastodon if you only rely on the protocol specs, that they do things their own way and have different requirements than the official specs.

Is this still a problem? If it is, are Mastodon moving to be more closely aligned with the spec, or to doing more of their own thing?

From what I've seen, Mastodon sticks to the spec but a lot of clients and servers then stick to Mastodon's interpretation of the spec rather than the spec. e.g. for status IDs, the spec says "String (cast from an integer but not guaranteed to be a number)", Mastodon uses numerical IDs, some clients[1] see this as "Ah, IDs are numbers!" and break horribly when they're not numerically parseable (Akkoma, Pleroma, GotoSocial...)

(IIRC there was another thing where `created_at` is described as "The date when this status was created" but the type is given as "String (ISO 8601 Datetime)" which led some code to crash when Mastodon started outputting just dates instead of datetimes.)

[1] Including some from people who Really Should Know Better.

I like ActivityPub overall, but there are a lot of places where the spec is just too complex, and I suspect that contributed to a lot of the choices to implement whatever currently works with Mastodon instead of the spec.

I'm currently implementing parts of the spec, and there are parts (like fully handling context correctly) that feels like far more pain than it is worth vs. just handling occasional breakage.

It feels like a very ivory tower spec of the kind you wouldn't be likely to write if you built a complete reference implementation first.

But it's very on-brand as a W3C spec.

I'd love to see a revision that deprecates and simplifies a whole lot of things.

> I'd love to see a revision that deprecates and simplifies a whole lot of things.

The hidden complexities in AP have led to several efforts. In the past there has been LitePub [0]. A recent project is Versia [1]. And who knows there may be a FeatherPub [2] one day. If anyone knows of other attempts I'd like to hear.

[0] https://litepub.social/

[1] https://versia.pub/

[2] https://docs.google.com/document/d/13LuB6Z-C_drCLCEuCtNApX98...

Thanks. I remember looking at Litepub. Not aware of the other two. The FeatherPub document feels like by far the most useful.

But I also think just going through the spec with a red marker would be a useful exercise and maybe I will one day.

In the sense that there are a whole lot of features nobody does anything useful with.

E.g. "@context" in theory provides a whole lot of ways to type the rest of the data. I'd be willing to bet that you'd break a whole lot of software if you served up a "@context" for an actor that mapped common field-names in use by Mastodon to a different namespace and mapped the Mastodon features to different names...

In theory it's great. In practice, I suspect we have XML namespaces and people stupidly hardcoding prefixes all over again...

Ah, FeatherPub is in a google doc. That explains why I was having trouble googling it last night.

Also, there's a conversation happening about Versia today: https://social.coop/@smallcircles/113105954469059880

Yes, there's a related google doc delving into the data model:

https://docs.google.com/document/d/13mtl9gFmcuL-0MS-Boaeh3i6...

OP is a link to the atproto site because it got a major new revision within the last week

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