BillionMail: self-host an email platform and campaign workflow

BillionMail combines a mail server, newsletters, and email marketing in an open-source, self-hosted package. Its repository outlines a setup flow connecting a domain and DNS verification to campaign creation and sending, with list and tag management.

The project supports Docker and installation through aaPanel. It also integrates RoundCube for webmail, offers delivery analytics, and is licensed under AGPLv3; the team running it remains responsible for hosting the service.