Mobilizon is some groups server marketed as an events server (you can create events as yourself or as a group) which is built with Pleroma as starting point and looks very very good. I tried to use the demo instance, but failed in a few things, Like following a group from Friendica, becoming a member from Friendica and deleting a group.

The self hosting instructions seem very clear and are basically the same as Pleroma. It allows having multiple identities (profiles) to separate your professional and friends interactions, like Friendica used to have.

I'll look into it again another time.
joinmobilizon.org/en/

#JoinMobilizon - Let’s take back control of our events

A user-friendly, emancipatory and ethical tool for gathering, organising, and mobilizing.

^{joinmobilizon.org}