Mail-in-a-Box

Against what buyers need

Email server: covers 86% of the checklist. Turns a fresh Ubuntu server into a mail host with Roundcube, Nextcloud contacts and calendar, Z-Push ActiveSync, spam filtering with greylisting, automatic DNS for SPF, DKIM, DMARC and MTA-STS, backups and a control panel with TOTP 2FA. It is deliberately not configurable and is maintained by volunteers, so it suits a person or small group more than a company with policies to enforce. Missing: end-to-end or PGP encryption and high-volume sending.

Judgement

What it is

Complete system

What it does

A setup script that turns a fresh Ubuntu server into a complete mail server with Postfix, Dovecot, Roundcube webmail, Nextcloud contacts and calendars, spam filtering, DNS and TLS.

Adopt it when

You want your own email on a dedicated VPS with as few decisions as possible.

Watch out

It takes over the whole machine, allows almost no customisation, and depends on a specific Ubuntu LTS release.

Ready for

Production-ready

Runs as

Self-hosted server

Built with

Python, Shell, Postfix, Dovecot, Roundcube and Nextcloud

How established

Established: started 13 years ago, latest release v77.

What the license allows

You can take the code into anything, including a product you sell, with no conditions.

Judged on 2026-11-06 from the project's README and GitHub data. The license and age lines are worked out directly.

Compare Mail-in-a-Box

Built from

Follow it down: Mail-in-a-Box → CPython → GCC → LLVM project → runs on a microchip

How compilers were built, back to punched paper tape

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