Mailu vs Postal
| Tagline | Simple yet full-featured mail server as a set of Docker images | Self-hosted mail delivery platform, a SendGrid/Mailgun alternative |
| Category | Email & Newsletters | Email & Newsletters |
| Replaces | Gmail / Google Workspace | SendGrid |
| GitHub stars | 7.5k | 17k |
| Language | Python | Ruby |
| License | MIT | MIT |
| Self-host difficulty | 3/5 Moderate | 4/5 Involved |
| Deploy options | Docker Compose Kubernetes Manual | Docker Docker Compose Manual |
| Managed hosting | ||
| Last updated | 3 days ago | 2 days ago |
| View repo | View repo |
Where each falls short
The honest trade-offs — what you give up with each, versus the proprietary tools they replace.
Mailu
- No calendar/contacts groupware bundled by default
- Requires correct DNS, PTR, and IP reputation to deliver reliably
- Focused on mailboxes, not newsletters or marketing campaigns
- Upgrades occasionally require manual migration steps
Postal
- You are responsible for IP reputation, warmup, and deliverability
- Requires MariaDB, RabbitMQ, and DNS/DKIM configuration to run
- No marketing-campaign UI — it is a delivery engine, not a newsletter builder
- Less hand-holding than managed providers for spam/blocklist issues
Bottom line
Choose Mailu if you want the lower-effort setup; choose Postal for the larger community and ecosystem. Postal has seen more recent development. Open each guide below for deploy steps and the full feature gap.