I setup my own @npub1m9z3...whzq server, using my own #nextcloud server as authentication source.
The geeky setup and configuration is described in some notes, in case someone else (or a future me) wants to do that too. Improvement suggestions welcome.

Matrix with MAS & Nextcloud setup - HedgeDoc
I run my own synapse homeserver, and use my Nextcloud server to authenticate, allowing me to e.g. make use of 2FA.