module:hook("muc-occupant-joined", function (event)

	local room = event.room;

	local occupant_jid = event.occupant.bare_jid;

	local aff = room:get_affiliation(occupant_jid);

	if aff then return; end -- user already registered

	module:log("debug", "Automatically registering %s as a member in %s", occupant_jid, room.jid);

	room:set_affiliation(true, occupant_jid, "member");

end);