Overview

Maddy is a composable, all-in-one mail server written in Go. A single binary combines an SMTP server (MTA), message submission and an IMAP server (MDA), letting you run a complete mail stack with one lightweight daemon and one configuration file.

Key Features

• Single Binary: SMTP, submission and IMAP in one composable daemon
• Composable Design: mail flow assembled from modular endpoints and pipelines
• Automatic TLS: certificates obtained and renewed automatically
• Flexible Storage: local filesystem, SQL, or remote IMAP backends for mail
• Extensible Auth: external authentication checkers and sub-addressing (plus-addressing) support
• Lightweight: low memory footprint and simple deployment

Why Use It

Maddy is for people who want a mail server that is small, fast and easy to understand. Because everything ships in one Go binary with a single readable config, it is far simpler to deploy and reason about than a conventional Postfix/Dovecot combination.

Use Cases

• Running a small or personal mail server with minimal resources
• Self-hosting email on a low-powered VPS or single-board computer
• Configuring a custom, composable mail flow with fine-grained control

Platforms

Linux and other Unix-like systems (single static binary; also official Docker images).

Licence

Open Source — GPL-3.0.

Website

https://maddy.email/

Alternatives

• Mailcow — dockerised all-in-one mail server suite