WHAT IS IT?
BillionMail bundles a full mail server (Postfix, Dovecot, Rspamd) and an email marketing platform into a single Docker deployment. You get SMTP, RoundCube webmail, a campaign manager, and an analytics dashboard — all running on your own hardware with no monthly subscription.
The backend is written in Go (92% of the codebase), with MariaDB for storage. Installation goes through Docker Compose or a bash script that takes roughly 8 minutes. The project sits at 13.7k GitHub stars and the latest release is v4.9.
WHY IS IT INTERESTING?
No per-volume billing. Where Mailchimp or SendGrid charge per email sent, BillionMail has no built-in sending limits. You pay for your server, period. For anyone pushing serious volume, the cost difference is immediate.
Production-ready mail stack without the assembly. Setting up Postfix + Dovecot + Rspamd + spam filtering + webmail by hand is easily a full day of work (and weeks of debugging). BillionMail packages everything into orchestrated containers. DNS records (SPF, DKIM, DMARC) are verified from the UI and SSL is configured automatically.
Native email marketing built in. This isn't just an SMTP server. You get a template editor, list segmentation, personalization variables, spintax support, and scheduled sending. The dashboard shows deliverability, open rates, and click-through rates in real time. Think self-hosted Mailchimp.
Webmail included. RoundCube is integrated and accessible at /roundcube/. Your team can read and send emails without an external client.
USE CASES
- Send newsletters to your user base without SaaS dependency or volume caps
- Handle transactional emails (signup confirmation, password reset) from your own infrastructure
- Run outreach campaigns with personalization and metric tracking
- Host your team's email with built-in webmail on your own domain
- Replace a paid email service when per-volume pricing no longer makes sense