Self-Hosted Email Server Stacks

Mailu is a complete email distribution system deployed as a suite of containerized images. It provides a self-hosted email infrastructure that integrates a webmail client interface with a centralized administration dashboard for managing domains, user accounts, and storage quotas. The system focuses on email deliverability and security through a framework that implements identity verification records and digital certificates. This includes the use of identity signatures and encryption to secure mail transport and prevent domain spoofing. The platform includes layered spam and malware filteri

Mail-in-a-Box is a self-hosted email server appliance that automates the deployment of SMTP, IMAP, and POP3 services on Linux. It functions as a complete suite including a DNS management server, a spam and abuse filter, and a web-based administrative control panel for managing users, aliases, and storage quotas. The project distinguishes itself through a high degree of automation for email security and authenticity. It automatically provisions and maintains SPF, DKIM, DMARC, and DNSSEC records to prevent domain spoofing, while managing the installation and rotation of TLS certificates and enf

BillionMail is a self-hosted email infrastructure and marketing platform designed to provide full control over mail delivery, domain management, and subscriber communication. It functions as a comprehensive mail server manager that enables users to deploy and maintain private email environments, including integrated webmail interfaces for direct account access. The platform distinguishes itself by combining high-volume bulk email distribution with sophisticated deliverability tools. It supports multi-tenant infrastructure provisioning, allowing administrators to manage multiple domains and ma

Stalwart is a self-hosted email and collaboration infrastructure that provides an integrated mail server supporting SMTP, IMAP, POP3, and JMAP protocols. It functions as a comprehensive communication hub, combining email hosting with a collaboration server for shared calendars, contacts, and files. The system distinguishes itself through a distributed architecture that uses peer-to-peer cluster coordination to ensure high availability and fault tolerance. It features a built-in security suite that implements an S/MIME and OpenPGP email gateway alongside automated TLS certificate provisioning

Mox is a self-hosted email server that runs as a single compiled Go binary, handling the full lifecycle of sending and receiving email through SMTP, IMAP4rev2, and a built-in webmail application. It is designed to be operated without external dependencies or runtime plugins, with all mail services — including spam filtering, queue management, and web interfaces for administration and account management — contained in one executable. The server distinguishes itself through automated TLS certificate management via ACME, DNS-based autoconfiguration for email clients, and file-based configuration

Mailcow-dockerized is an open-source email hosting platform that provides a complete, self-hosted infrastructure suite. It bundles message transfer, storage, and security protocols into a modular, containerized environment designed for deployment on private infrastructure. The platform distinguishes itself by integrating a centralized management interface for configuring mail domains and user accounts alongside collaborative tools like shared calendars and contact lists. It includes automated security features such as integrated spam and malware filtering gateways, as well as automated certif

Mail hosting made simple

Maddy is a modular mail server that assembles a complete email system by connecting small, single-purpose modules through a declarative configuration file. Rather than a monolithic stack, it lets operators compose message processing, storage, authentication, and security enforcement from interchangeable building blocks, with each module handling a specific function like receiving SMTP connections, verifying credentials, or applying policy checks. The server distinguishes itself through its flexible authentication and security architecture. It delegates user verification to external systems in

This project provides a full-stack, containerized mail server platform designed for self-hosting. It functions as a complete mail transfer agent that bundles essential services—including SMTP, IMAP, and POP3—into a unified environment. By leveraging container orchestration, it enables the deployment of private email infrastructure that handles message transport, delivery, and user management within a single, manageable service. The platform distinguishes itself through deep integration with container runtimes and robust configuration flexibility. It supports granular customization via configu

Full-featured, open source mail server solution for mainstream Linux/BSD distributions.

This project is an email alias management platform and masking proxy designed to protect user privacy. It functions as a gateway that creates unique email addresses to hide a user's primary mailbox, forwarding incoming messages while routing outbound replies through a reverse-proxy to maintain sender anonymity. The system distinguishes itself through advanced domain and privacy controls, including the ability to link personal domains via DNS for branded aliases and catch-all routing. It further secures communications via a PGP encryption gateway that encrypts forwarded email content using pub