Abstract Finding a combination between privacy and accountability in the online world is a challenge. Too little accountability supports problematic behaviour. Too little privacy undermines individual freedom and has a chilling effect. This paper describes the identity infrastructure of a new open source community platform called PubHubs. It combines local group conversations, via its own adaptation of Matrix, with proportional authentication of users, in local identity spaces. PubHubs thus achieves a combination of privacy and accountability. The technical core of the paper describes the cryptographic protocols for managing digital identities, via both personal attributes and local pseudonyms. Around this core, the roles of digital identities within the PubHubs platform are explained in functional terms, giving participants for instance more certainty about others in a conversation, or giving moderators new tools.