>when building a social app, you always need user authentication, friends lists, collections, ratings, comments ... I think that presupposes what the task will

>when building a social app, you always need user authentication, friends lists, collections, ratings, comments ... I think that presupposes what the task will be too much. It is facilitating social apps as they are today rather than how they could be. At the fundamental level, what is needed is Authentication and authorised data access. The authorisation system is one where data can be conditionally detected, accessed and modified by specific identities. That will allow friends lists, collections, ratings, comments etc. without dictating the form those things should take. The authorisation mechanism is a hard problem™. I think it isn't impossible though.