This is shameless self-promotion, but part of a working theory I have that Mastodon users have more to offer Lemmy than your average Reddit user. See my other post about it here: lemmy.blahaj.zone/post/2174573...
It will be open source, end to end encrypted using Signal’s double ratchet encryption protocol, and he plans to make it easy for fediverse platforms to integrate it. The beta will release later this month....