I think we are very close to going live with a mailman-users(a)mailman3.org list.
I am comfortable that between Postorius and mailman shell I can create and configure the list. The HyperKitty issues that were blockers for me have been fixed.
The one remaining blocker that I see[1] is that Google login doesn't work. This is reported here https://gitlab.com/mailman/hyperkitty/issues/73
I have been playing with this. I gave up on Google OpenID and tried configuring Google OAuth2 and Twitter OAuth. I've actually got Google working, so bang on it some. I'm close with Twitter, the issue is it gets all the way back but something is missing when HyperKitty tries to get the user record. The last few lines of the traceback are: File "/usr/local/lib/python2.7/dist-packages/HyperKitty-1.0.4-py2.7.egg/hyperkitty/lib/mailman.py", line 155, in add_user_to_mailman mm_user = profile.get_mailman_user() File "/usr/local/lib/python2.7/dist-packages/HyperKitty-1.0.4-py2.7.egg/hyperkitty/models/profile.py", line 91, in get_mailman_user mm_user = mm_client.get_user(self.user.email) File "/usr/local/lib/python2.7/dist-packages/mailmanclient-1.0.1-py2.7.egg/mailmanclient/_client.py", line 514, in get_user return User(self._connection, content['self_link'], content) KeyError: u'self_link'