mail-in-a-box/mailinabox

Mail-in-a-Box is a Python-based project that automates the setup of a complete, self-hosted email server. The idea is that rather than relying on Gmail, Outlook, or another email provider, you can run your own email on a server you control. The README describes its goals as making it easy to deploy a good mail server, promoting decentralization and privacy, and having a configuration that is automated and repeatable. Starting from a fresh Ubuntu 22.04 LTS machine, running the setup script installs and configures a large collection of components that together make a fully working mail server. On the mail side: Postfix handles sending mail (SMTP -- the protocol emails travel over), Dovecot handles receiving and storing mail (IMAP), and Roundcube provides a webmail interface accessible in a browser. For calendar and contacts sync, Nextcloud provides CardDAV/CalDAV, and z-push adds Exchange ActiveSync compatibility. Spam is filtered using SpamAssassin and postgrey. Security and DNS are handled automatically: Let's Encrypt (a free certificate authority) provisions TLS certificates for all services, and the DNS server is configured with SPF, DKIM, DMARC, DNSSEC, and other email authentication records that help other servers trust mail coming from your server. Backups are handled by duplicity, with fail2ban providing intrusion protection. A built-in web control panel lets you add and remove email users, create aliases, manage DNS records, and configure backups. There is also an API for all control panel functions. The project explicitly states it is not customizable by power users and intentionally has no user-configurable setup options -- it is designed to just work.