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Self-Hosted Security Communication Email Networking Mail Server

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Last Updated: 08-22-2026 05:56 PM (UTC)

Mox

Mox offers a complete mail server stack in a single Go binary requiring no external dependencies. The quickstart command configures a working mail server with SMTP, IMAP4, webmail, and full DNS authentication in under ten minutes. SMTP handling includes a delivery server on port 25, a submission server for authenticated clients, and a queue with automatic retries and DKIM signing. IMAP4rev2 implementation provides full mailbox synchronization with CONDSTORE and QRESYNC for efficient offline clients, NOTIFY for multi-mailbox monitoring, MULTISEARCH across mailboxes, and TLS client certificate authentication via the EXTERNAL SASL mechanism. The built-in webmail provides browser-based reading and composing with message threading, attachments, and HTML rendering without requiring a separate web client. Email authentication implements SPF validation, DKIM signing and verification with automatic key rotation, DMARC policy enforcement with aggregate and failure reporting, DANE with DNSSEC-protected TLSA records, and MTA-STS for certificate verification. Junk filtering combines reputation-based sender scoring with Bayesian content analysis trained per account. The web administration interface manages domains, accounts, DNS records, TLS certificates, delivery queue, and real-time log viewing. Internationalized email addresses with EAI and IDNA support handle non-ASCII domains and mailboxes. Account autoconfiguration publishes settings for Thunderbird autoconfig and Outlook autodiscover. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. MIT licensed.

Mox
Mox
Mox
Mox
Mox

Benefits

  • Complete Mail Server in One Binary
  • Single Go binary provides SMTP, IMAP4rev2, webmail, junk filtering, TLS management, and web administration with zero external dependencies or separate service configuration.
  • Full Email Authentication Stack
  • SPF, DKIM with automatic key rotation, DMARC with aggregate reporting, DANE with DNSSEC-protected TLSA records, and MTA-STS provide maximum deliverability and security.
  • Ten-Minute Quickstart Setup
  • The quickstart command generates configuration, DNS records, and TLS certificates automatically, producing a fully operational mail server within ten minutes of installation.
  • Modern IMAP4rev2 Implementation
  • CONDSTORE, QRESYNC, NOTIFY for multi-mailbox monitoring, MULTISEARCH, and TLS client certificate authentication provide efficient synchronization for desktop and mobile clients.

Features

  • Built-In Webmail
  • Browser-based email client with message threading, HTML rendering, attachments, and compose interface requiring no separate webmail application installation.
  • Junk Filtering
  • Reputation-based sender scoring combined with per-account Bayesian content analysis automatically classifies spam without external filtering services.
  • Web Administration Interface
  • Manage domains, accounts, DNS records, TLS certificates, delivery queues, and view real-time logs through the browser-based admin panel.
  • Automatic TLS with ACME
  • Let's Encrypt integration generates and renews TLS certificates automatically for all configured domains without manual certificate management.
  • Account Autoconfiguration
  • Publishes Thunderbird autoconfig and Outlook autodiscover settings so email clients configure server connections automatically without manual entry.