Mailu

Mailu provides a self‑hosted mail server built from a collection of Docker images, allowing users to deploy a complete email solution without proprietary components. It supports standard protocols such as IMAP, IMAP+, SMTP and Submission, and offers auto‑configuration profiles for client setup. The system includes advanced features like aliases, domain aliases, custom routing, and full‑text search of attachments, as well as multiple webmail interfaces and an administrative dashboard.

Administrators can manage global settings, per‑domain delegation, quotas, and announcements, while users benefit from auto‑reply, forwarding, fetched accounts and Manageieve filtering. Security is addressed through enforced TLS, DANE, MTA‑STS, Let’s Encrypt certificates, outgoing DKIM, an integrated antivirus scanner, and protection against malicious attachments. Antispam capabilities include auto‑learning, greylisting, DMARC, SPF and anti‑spoofing checks.

All components are released under the MIT license, making the project free software that can be freely modified and redistributed. Documentation is maintained alongside the code, and the community welcomes contributions and support via Matrix.