docs: add federation.md

FEDERATION.md

@@ -0,0 +1,31 @@
+# Federation in Hatsu
+
+## Supported federation protocols and standards
+
+- [ActivityPub](https://www.w3.org/TR/activitypub/) (Server-to-Server)
+- [Http Signatures](https://datatracker.ietf.org/doc/html/draft-cavage-http-signatures)
+- [WebFinger](https://webfinger.net/)
+- [NodeInfo](https://nodeinfo.diaspora.software/)
+- [Web Host Metadata](https://datatracker.ietf.org/doc/html/rfc6415)
+
+## Supported FEPs
+
+- [FEP-67ff: FEDERATION.md](https://codeberg.org/fediverse/fep/src/branch/main/fep/67ff/fep-67ff.md)
+- [FEP-f1d5: NodeInfo in Fediverse Software](https://codeberg.org/fediverse/fep/src/branch/main/fep/f1d5/fep-f1d5.md)
+<!-- - [FEP-fffd: Proxy Objects](https://codeberg.org/fediverse/fep/src/branch/main/fep/fffd/fep-fffd.md) -->
+
+## ActivityPub
+
+The following activities and object types are supported:
+
+- `Follow(Actor)`, `Undo(Follow)`
+- `Create(Note)`
+<!-- - `Create(Note)`, `Update(Note)`, `Delete(Note)` -->
+<!-- - `Like(Note)`, `Undo(Like)` -->
+<!-- - `Announce(Note)`, `Undo(Announce)` -->
+
+Activities are implemented in way that is compatible with Mastodon and other popular ActivityPub servers.
+
+### Notable differences
+
+- No shared inbox.

docs/src/SUMMARY.md

@@ -32,4 +32,5 @@
 # Others
 
 - [Compatibility Chart](./others/compatibility-chart.md)
+- [Federation](./others/federation.md)
 - [JSON Feed Extension](./others/json-feed-extension.md)

docs/src/others/federation.md

@@ -0,0 +1,31 @@
+# Federation in Hatsu
+
+## Supported federation protocols and standards
+
+- [ActivityPub](https://www.w3.org/TR/activitypub/) (Server-to-Server)
+- [Http Signatures](https://datatracker.ietf.org/doc/html/draft-cavage-http-signatures)
+- [WebFinger](https://webfinger.net/)
+- [NodeInfo](https://nodeinfo.diaspora.software/)
+- [Web Host Metadata](https://datatracker.ietf.org/doc/html/rfc6415)
+
+## Supported FEPs
+
+- [FEP-67ff: FEDERATION.md](https://codeberg.org/fediverse/fep/src/branch/main/fep/67ff/fep-67ff.md)
+- [FEP-f1d5: NodeInfo in Fediverse Software](https://codeberg.org/fediverse/fep/src/branch/main/fep/f1d5/fep-f1d5.md)
+<!-- - [FEP-fffd: Proxy Objects](https://codeberg.org/fediverse/fep/src/branch/main/fep/fffd/fep-fffd.md) -->
+
+## ActivityPub
+
+The following activities and object types are supported:
+
+- `Follow(Actor)`, `Undo(Follow)`
+- `Create(Note)`
+<!-- - `Create(Note)`, `Update(Note)`, `Delete(Note)` -->
+<!-- - `Like(Note)`, `Undo(Like)` -->
+<!-- - `Announce(Note)`, `Undo(Announce)` -->
+
+Activities are implemented in way that is compatible with Mastodon and other popular ActivityPub servers.
+
+### Notable differences
+
+- No shared inbox.