Recently, there was a discussion about generic #ActivityPub servers. Several people claimed that they were working on one, but it turned out that their "generic" servers only support activities defined in the ActivityPub specification. Such a server shouldn't be called generic. It is not difficult to build, neither it is an interesting concept because competing protocols (e.g. Nostr) already offer much more.

I've been writing a #FEP that describes how to build a real generic server. It is not finished yet, but I feel like now is a good time to publish it:

FEP-fc48: Generic ActivityPub server

This kind of server:

- Can process any object type, and can process non-standard activities like EmojiReact.
- Compatible with FEP-ae97 clients.
- Does not require JSON-LD.

I attempted to implement it when I was researching security properties of FEP-ae97 API: https://codeberg.org/silverpill/fep-ae97-server. Back then I didn't know what to do with side effects, but now I think that we can simply force clients to specify them.

Special thanks to @mariusor and @trwnh for their input.

#C2S

Recently, there was a discussion about generic #ActivityPub servers. Several people claimed that they were working on one, but it turned out that their "generic" servers only support activities defined in the ActivityPub specification. Such a server shouldn't be called generic. It is not difficult to build, neither it is an interesting concept because competing protocols (e.g. Nostr) already offer much more.

I've been writing a #FEP that describes how to build a real generic server. It is not finished yet, but I feel like now is a good time to publish it:

FEP-fc48: Generic ActivityPub server

This kind of server:

- Can process any object type, and can process non-standard activities like EmojiReact.
- Compatible with FEP-ae97 clients.
- Does not require JSON-LD.

I attempted to implement it when I was researching security properties of FEP-ae97 API: https://codeberg.org/silverpill/fep-ae97-server. Back then I didn't know what to do with side effects, but now I think that we can simply force clients to specify them.

Special thanks to @mariusor and @trwnh for their input.

#C2S

The intro to HDA (Hypermedia-Driven Applications) I've been raving about today seems relevant to the ongoing discussions about C2S APIs for the fediverse, especially the proliferation of the monolithic server+web-app antipattern. I've started a SH topic on it;

https://socialhub.activitypub.rocks/t/could-hypermedia-driven-application-architecture-be-useful-for-ap-c2s/8521

But SH seems like a ghost town ATM. Tried to post on ActivityPub.space but their interface hates my mobile browser (Fennec from F-Droid) 🤷‍♂️

#FediDevs #ActivityPub #C2S

ActivityPub client developer experience is something like this.

Building a coherent feed with stateful objects requires comparing an Activity from the inbox, with what’s in your outbox.

#ActivityPub #c2s #DevEx

ActivityPub client developer experience is something like this.

Building a coherent feed with stateful objects requires comparing an Activity from the inbox, with what’s in your outbox.

#ActivityPub #c2s #DevEx

I opened a issue in the swicg ActivityPub API repo about a gap i keep running into: how does a C2S client access server-local metadata about foreign objects?

Thread collections, read status, notifications — your server knows things about remote objects that the client needs, but AP has no vocabulary for it.

https://github.com/swicg/activitypub-api/issues/60

#ActivityPub #Fediverse #C2S

@evanprodromou

Have I already mentioned that the “Show thread” request is slowly driving me crazy?

#c2s #activityPub #fep7888

Have I already mentioned that the “Show thread” request is slowly driving me crazy?

#c2s #activityPub #fep7888

I opened a issue in the swicg ActivityPub API repo about a gap i keep running into: how does a C2S client access server-local metadata about foreign objects?

Thread collections, read status, notifications — your server knows things about remote objects that the client needs, but AP has no vocabulary for it.

https://github.com/swicg/activitypub-api/issues/60

#ActivityPub #Fediverse #C2S

@evanprodromou

@django @evan @liaizon

Hey, this is great. It is so nice to see the uptick of interest in the #C2S part of #ActivityPub. Very uplifting and gives me hope for the future of #fediverse.

I really liked your #FOSDEM presentation, and thank you for mentioning my humble list. They are just notes atm, but I will try to keep them up-to-date. I just made a bunch of updates..

https://codeberg.org/fediverse/delightful-fediverse-experience/issues/130

Would love to hear more on what are the particular plans and goals for your project in the near future?

@django @evan @liaizon

Hey, this is great. It is so nice to see the uptick of interest in the #C2S part of #ActivityPub. Very uplifting and gives me hope for the future of #fediverse.

I really liked your #FOSDEM presentation, and thank you for mentioning my humble list. They are just notes atm, but I will try to keep them up-to-date. I just made a bunch of updates..

https://codeberg.org/fediverse/delightful-fediverse-experience/issues/130

Would love to hear more on what are the particular plans and goals for your project in the near future?

@kopper @nelson

This is marvelous. I wasn't aware of your project, but now I am and added it to the #ActivityPub #C2S tracking list.

I've also lined up #Outpost for inclusion on the delightful #fediverse curated lists at https://delightful.coding.social

Bring it on!

#ActivityPub Social API is getting a lot of attention and traction on the implementation side! 🎉

Join the fun, in this area where there's a fine future for the #fediverse social networking.

Some new updates to the list of client-to-server #C2S parts of the AP open standard:

https://codeberg.org/fediverse/delightful-fediverse-experience/issues/130

Added the projects of @kopper and a new C2S article by @django

Bring it on!

#ActivityPub Social API is getting a lot of attention and traction on the implementation side! 🎉

Join the fun, in this area where there's a fine future for the #fediverse social networking.

Some new updates to the list of client-to-server #C2S parts of the AP open standard:

https://codeberg.org/fediverse/delightful-fediverse-experience/issues/130

Added the projects of @kopper and a new C2S article by @django

@pfefferle @steve @mariusor

This is wonderful! I updated my #ActivityPub #C2S notes with link to the PR..

https://codeberg.org/fediverse/delightful-fediverse-experience/issues/130

thanks to the awesome support of @steve and @mariusor the #WordPress #ActivityPub #C2S API support is quite solid now.

It is possible to publish a new post, comment to posts and other comments and to follow others.

https://github.com/Automattic/wordpress-activitypub/pull/2851

thanks to the awesome support of @steve and @mariusor the #WordPress #ActivityPub #C2S API support is quite solid now.

It is possible to publish a new post, comment to posts and other comments and to follow others.

https://github.com/Automattic/wordpress-activitypub/pull/2851

@i47i @HolosSocial @apps

PS. I track a list of #ActivityPub #C2S implementations and didn't add #Holos till now. If I should add it, pleas let me know, or comment directly to the issue.

https://codeberg.org/fediverse/delightful-fediverse-apps/issues/130

My fosdem talk is up!

I make a case for more platforms to support the ActivityPub client API, and how we should look beyond microblogging for future growth of the ‘verse

https://fosdem.org/2026/schedule/event/QK7XSV-activitypub-c2s/

#c2s #fosdem #fediverse #ActivityPub