Maddy
A composable, all-in-one mail server that implements SMTP, IMAP, DKIM, SPF, DMARC, and more in a single daemon.
What is Maddy?
Maddy is a composable, all-in-one mail server that implements the full email stack in a single daemon. It handles SMTP for sending and receiving messages, provides IMAP storage, and integrates security protocols like DKIM, SPF, and DMARC to ensure secure email delivery. It aims to replace traditional multi-component setups with a unified, low-maintenance solution.
System administrators, developers, or organizations looking to self-host a complete email server with simplified configuration and maintenance. It's ideal for those wanting to consolidate tools like Postfix and Dovecot into one system.
Developers choose Maddy because it replaces multiple separate email server components with a single, cohesively configured daemon, reducing complexity and maintenance overhead while still providing essential email functionality and security.
Overview
✉️ Composable all-in-one mail server.
Use Cases
Best For
- Self-hosting a complete email server for personal or organizational use
- Replacing traditional multi-component setups like Postfix + Dovecot + OpenDKIM
- Simplifying email server configuration and maintenance
- Implementing email security protocols (DKIM, SPF, DMARC) in a unified way
- Setting up an SMTP MTA and MX with integrated security features
- Running a low-maintenance mail server with a single daemon
Not Ideal For
- Environments requiring stable, production-ready IMAP storage for critical email access
- Teams deeply invested in Postfix or Dovecot ecosystems with custom plugins or configurations
- High-volume email services where scaling individual components separately is a priority
- Projects needing a built-in webmail interface or extensive third-party integrations
Pros & Cons
Pros
Consolidates multiple daemons like Postfix and Dovecot into a single process, dramatically reducing deployment complexity and setup time.
Uses one consistent configuration system across all email functions, minimizing administrative overhead and error-prone setups.
Implements DKIM, SPF, DMARC, DANE, and MTA-STS out of the box, ensuring email deliverability and compliance without extra tools.
Designed as a composable, minimal-maintenance solution, ideal for self-hosters who want to reduce ongoing server management.
Cons
The IMAP feature is explicitly labeled as beta in the README, making it less stable and feature-complete compared to alternatives like Dovecot.
As a newer, integrated tool, it lacks the extensive plugins, community support, and battle-testing of established components like Postfix.
While unified, the configuration system can be complex for users accustomed to the separate, well-documented setups of traditional tools.
Open Source Alternative To
Maddy is an open-source alternative to the following products:
OpenSPF is an open-source implementation of the Sender Policy Framework (SPF) for email authentication, used to validate sender IP addresses against domain policies.
OpenDKIM is an open-source implementation of the DomainKeys Identified Mail (DKIM) standard for email authentication.
Postfix is a free and open-source mail transfer agent (MTA) that routes and delivers electronic mail on Unix-like operating systems.
OpenDMARC is an open-source implementation of the Domain-based Message Authentication, Reporting, and Conformance (DMARC) standard for email security.
Dovecot is an open-source IMAP and POP3 email server for Linux/UNIX-like systems, focusing on security and performance.
Frequently Asked Questions
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