Welcome to Stalwart

Welcome to Stalwart, an open-source mail and collaboration server designed for the modern internet. Stalwart supports a wide range of protocols including JMAP, IMAP4, POP3, SMTP, CalDAV, CardDAV, and WebDAV, making it a comprehensive solution for managing email, calendars, contacts, file storage, and more. Built in Rust, Stalwart is engineered to be secure, fast, robust, and scalable, capable of running everything from small personal mail servers to large, distributed enterprise deployments.

This Getting Started guide is intended to help new users install, configure, and optimize Stalwart for their specific needs. It walks through the essential steps and considerations for a successful deployment.

We begin with an overview of System Requirements, where you’ll learn how memory and CPU usage scale with server load and how to size your system accordingly. The Installation Guide provides instructions for setting up Stalwart on your platform of choice, including details on configuration.

Next, we explore how to choose the right database for your deployment, explaining Stalwart’s modular storage architecture and how to match different storage backends to the data they manage. You’ll also learn how to choose a directory, whether internal or external, for handling user authentication and account management.

Once the server is configured, proper DNS setup is crucial for ensuring secure and reliable mail delivery and client connectivity. This section explains all the DNS records required for services like SPF, DKIM, DMARC, MTA-STS, and more.

To ensure your deployment remains secure, we cover several best practices in the Securing Your Server section. This includes disabling unused ports, configuring HTTP access controls, and enforcing clear administrative roles to minimize risk and maintain operational integrity.

Finally, for large or high-traffic environments, the Performance Tuning section offers guidance on caching and concurrency settings, helping you get the best performance out of your server under demanding conditions.

Whether you're running a single-node setup or planning a distributed deployment, this guide will help you get Stalwart up and running efficiently and securely. Let’s get started.