KumoMTA

KumoMTA: Open Source Mail Transfer Agent

KumoMTA is an open source mail transfer agent designed to be lightweight, fast, and secure. It aims to provide a simple SMTP server for receiving, routing, and delivering email without unnecessary complexity.

What is KumoMTA?

KumoMTA is an open source mail transfer agent (MTA) designed specifically to be a fast, lightweight, and secure SMTP server solution. Unlike traditional MTAs like Postfix or Sendmail which come packed with lots of features, KumoMTA aims to provide only the core functionality required for a basic SMTP server.

Some key features and characteristics of KumoMTA include:

• Written in Rust for speed and security
• Simple configuration with reasonable defaults to be up and running quickly
• Uses modern asynchronous I/O for high performance
• Supports SMTP and LMTP delivery to mailboxes
• Validation of SMTP sessions with SPF, DKIM, and DMARC
• Greylisting and other techniques to improve security
• Pluggable architecture supports extensions with additional functionality
• Actively maintained and developed by Maildeliver team

Overall, KumoMTA is designed for use cases where you need to receive emails via SMTP and deliver them locally or remotely but don't want the complexity or overhead of heavier traditional MTAs. Its minimal resource usage and security hardening make it well suited for containerized environments, embedded devices, and microservices architectures.

KumoMTA Features

Official Links