If I understand correctly, ActivityPub implementation on Lemmy is just starting and is mostly dormant (which isn’t a dig on any of the developers since no one is getting paid to implement it). But is this because it’s hard to implement? Lack of knowledge? Or simply that no one has had the time to actually start implementing it? When we do get started, how big a project is it expected to be?
For a browseable ActivityPub service you can take a look at mine (probably you need a json beautifier extension in your browser):
Top level (a Service actor representing the server): https://federated.id
Actors collection (with filtering): https://federated.id/actors?type=Person&name=marius
Activities collection (with filtering): https://federated.id/activities?type=Create&type=Update
Objects collection (with filtering): https://federated.id/objects?type=Note