Mox

A Go mail server for people hosting email on their own domains, combining SMTP, IMAP, webmail, spam filtering and automatic TLS in one binary.

5.9k stars, 239 forks Go On GitHub since January 2023

Visit website View on GitHub How to run it

Mox at a glance

Open sourceYes, MITNo paid parts in the repository
Health59 of 100Actively developed
Self-hostingDockerCompose file, 1 service
InterfaceEnglish onlyNo translation files found
Issue repliesWithin ~9 daysMedian first reply; 38% of recent issues answered

What is Mox?

Mox bundles the parts of a self-hosted email setup into one program. It receives, submits and delivers mail over SMTP, serves mailboxes over IMAP, and includes webmail for the browser. Junk handling relies on per-user Bayesian filtering and reputation learned from how users classify messages, and slows down unknown senders much like greylisting. SPF, DKIM, DMARC, DANE, MTA-STS and TLS reports are built in, and certificates come from Let's Encrypt via ACME. A mox quickstart command writes the configuration, creates an account and prints the DNS records to add. There is also a web admin panel, a reverse-proxying web server, metrics and an HTTP API with webhooks for transactional mail.

Good fit if

  • You want to move your domain's mail off a paid provider and prefer one binary over a stack of separate daemons.
  • You have a dedicated machine or VM for mail and want guided DNS and TLS setup.
  • Your applications need an HTTP API for sending messages and receiving delivery events.

Look elsewhere if

Before you adopt it

Mox is MIT-licensed, and the repository contains no paid parts. Mechiel Lukkien created it and writes most of the code, about nine in ten recent commits, with grants from NLnet and the EU NGI programme. Releases are still numbered 0.0.x; the latest is v0.0.17 from August 2026. It runs fully only on Unix systems. A Docker image exists, though the README does not recommend it and requires host networking if you use it. Plan on a machine without another web server on ports 80 and 443.

Drafted with AI from the project's README and repository data, then checked against that data on 7 November 2026. Report a correction

How to run Mox yourself

One-click install

Not listed in the app catalogs of Umbrel, YunoHost, TrueNAS, Unraid, CasaOS, Runtipi, Proxmox VE Helper-Scripts and Coolify.

Ways to install

Docker files
Dockerfile or compose file in the repository
Compose file
docker-compose.yml: 1 service
Setup effort
1 of 5, judged from the compose file
Kubernetes
No Helm chart in the repository
Packages
AUR, Nix, Homebrew and MacPorts versions on Repology
Desktop and mobile
No app builds in GitHub releases
Interface languages
English only

Install instructions: xmox.nl or the README on GitHub. Docker images and packages are checked weekly.

Mox health: is it still maintained?

59 of 100, actively developed

Release rhythmEvery ~50 days2 releases in 12 months; latest v0.0.17
Issue repliesWithin ~9 daysMedian first reply; 38% of recent issues answered
Bus factorHigh riskThe most active of 7 authors wrote 86% of recent commits
  • Activity
    43 commits in the last 90 days, the latest on 27 October 2026.
    20 / 30
  • Contributors
    7 people wrote the 43 commits of the last 90 days; the most active wrote 86% of them.
    12 / 20
  • Releases
    2 releases in the last 12 months; the latest, v0.0.17, on 19 August 2026.
    15 / 20
  • Replies to issues
    Maintainers answered 38% of recent issues, with a median first reply after 9 days.
    7 / 20
  • Security practices
    No OpenSSF Scorecard for this repository yet, so this part gets a neutral score.
    5 / 10

Read from GitHub on 12 November 2026. How the score works

Mox security

Security advisories are the vulnerabilities the maintainers disclosed on GitHub, with the versions that fix them; many advisories can mean careful disclosure as much as weak code.

Security advisoriesNone publishedNo advisories in the repository’s Security tab

Advisories read from GitHub on 12 November 2026.

Mox license: is it open source?

Mox uses MIT, an open-source license approved by the OSI.

  1. January 2023First published on GitHub.
  2. TodayMIT.

Mox for developers

Written in

  • Go 68%
  • TypeScript 16%
  • JavaScript 15%
  • Shell <1%
  • Makefile <1%
  • Other <1%

Getting involved

Contributing guideNot foundNo CONTRIBUTING file in the repository
Open issues196On GitHub
Authors, 90 days7Of 43 commits

Language shares are GitHub’s count of the code in the repository.

Alternatives to Mox

  • MailuInsular email distribution - mail server as Docker images 76 health · MIT · 7.6k stars
  • Stalwart Mail ServerAll-in-one Mail & Collaboration server. Secure, scalable and fluent in every protocol (IMAP, JMAP, SMTP,… 57 health · Unidentified license · 15.9k stars
  • Mail-in-a-BoxMail-in-a-Box helps individuals take back control of their email by defining a one-click, easy-to-deploy… 53 health · CC0-1.0 · 15.5k stars
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  • Maddy Mail ServerComposable all-in-one mail server. 73 health · GPL-3.0 · 6.1k stars

All 17 projects in Email servers & webmail

Questions about Mox

Is Mox open source?

Yes. Mox is published under MIT, an OSI-approved open-source license.

Is Mox still maintained?

Its health score is 59 of 100 (actively developed). It had 43 commits in the last 90 days, the latest on 27 October 2026, and its latest release came out on 19 August 2026.

How do I run Mox?

You can run it with Docker. The README on GitHub has the exact steps.

What is Mox written in?

Mox is written mainly in Go (68% of the code), with TypeScript (16%) and JavaScript (15%), by GitHub’s count of the repository.

What are the alternatives to Mox?

Close alternatives in the Email servers & webmail category include Mailu, Stalwart Mail Server, Mail-in-a-Box.