Postal

A self-hosted mail delivery platform for websites and web apps that send and receive email, an alternative to Sendgrid or Mailgun.

17k stars, 1.3k forks Ruby On GitHub since April 2017

Visit website View on GitHub How to run it

Postal at a glance

Open sourceYes, MITNo paid parts in the repository
Health45 of 100Actively developed
Self-hostingDockerCompose file, 2 services
InterfaceEnglish onlyNo translation files found
Issue repliesWithin ~5 hoursMedian first reply; 36% of recent issues answered

What is Postal?

Postal is a mail server built for applications rather than personal inboxes. Websites and web servers hand it outgoing messages for delivery, and it can also accept incoming mail on their behalf. Its authors position it as a replacement for hosted sending services such as Sendgrid, Mailgun and Postmark that you run on your own servers. Deployment uses Docker, with MySQL as the database.

Good fit if

  • You send transactional or bulk email from your own applications and want to stop paying a delivery service per message.
  • Your apps need to receive incoming email as well as send it.

Look elsewhere if

Before you adopt it

Postal is distributed under the MIT license, and the repository contains no paid parts. Development is slow at the moment: only three commits from two authors landed in the last 90 days, and most of them came from one developer. The latest release is 3.3.7 from June 2026. Expect to manage DNS, IP reputation and deliverability on your own, as with any self-run sending platform.

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 Postal 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
Docker image
ghcr.io/postalserver/postal: x86-64
Compose file
docker-compose.yml: 2 services (mysql)
Setup effort
2 of 5, judged from the compose file
Kubernetes
No Helm chart in the repository
Desktop and mobile
No app builds in GitHub releases
Interface languages
English only

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

Postal health: is it still maintained?

45 of 100, actively developed

Release rhythmEvery ~3 days3 releases in 12 months; latest 3.3.7
Issue repliesWithin ~5 hoursMedian first reply; 36% of recent issues answered
Bus factorMedium riskThe most active of 2 authors wrote 67% of recent commits
  • Activity
    3 commits in the last 90 days, the latest on 1 October 2026.
    7 / 30
  • Contributors
    2 people wrote the 3 commits of the last 90 days; the most active wrote 67% of them.
    6 / 20
  • Releases
    3 releases in the last 12 months; the latest, 3.3.7, on 3 June 2026.
    12 / 20
  • Replies to issues
    Maintainers answered 36% of recent issues, with a median first reply after 5 hours.
    15 / 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

Postal 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 advisories2 published1 high; all list a fixed version

Latest advisories

Advisories read from GitHub on 12 November 2026.

Postal license: is it open source?

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

  1. April 2017First published on GitHub.
  2. TodayMIT.

Postal for developers

Written in

  • Ruby 77%
  • Haml 15%
  • SCSS 6%
  • CoffeeScript <1%
  • HTML <1%
  • Other <1%

Getting involved

Contributing guideYesCONTRIBUTING.mdOpen issues51On GitHub
Authors, 90 days2Of 3 commits

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

Alternatives to Postal

  • docker-mailserverProduction-ready fullstack but simple mail server (SMTP, IMAP, LDAP, Antispam, Antivirus, etc.) running… 80 health · MIT · 19.7k stars
  • MailuInsular email distribution - mail server as Docker images 76 health · MIT · 7.6k stars
  • Maddy Mail ServerComposable all-in-one mail server. 73 health · GPL-3.0 · 6.1k 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

All 17 projects in Email servers & webmail

Questions about Postal

Is Postal open source?

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

Is Postal still maintained?

Its health score is 45 of 100 (actively developed). It had 3 commits in the last 90 days, the latest on 1 October 2026, and its latest release came out on 3 June 2026.

How do I run Postal?

You can run it with the Docker image ghcr.io/postalserver/postal. The README on GitHub has the exact steps.

What is Postal written in?

Postal is written mainly in Ruby (77% of the code), with Haml (15%) and SCSS (6%), by GitHub’s count of the repository.

What are the alternatives to Postal?

Close alternatives in the Email servers & webmail category include docker-mailserver, Mailu, Maddy Mail Server.