Modern Email Infrastructure


KumoMTA isn't just Open-Source, it's better by design.

Native Campaign Awareness

KumoMTA is natively aware of both campaigns and tenants, queueing them separately and enabling granular configuration and reporting. Tenants and IPs are de-coupled, providing a superior shared IP experience.

Automatic MX Rollup

Say goodbye to fractured configurations and out of date domain mapping tables, KumoMTA automatically identifies MX groups and queues messages together for common throttling and delivery.

OmniChannel Capable

KumoMTA not only supports IP pooling natively, but it's also built around channel extensibility, with support for HTTP, Kafka, and AMQP delivery of messages already available with more channels on the way.

Safe Performance

KumoMTA is not only capable of relaying millions of messages per hour, it does so without the risk that comes with deferred spooling. The speed you need, without the risk of data loss.

Modern Deployment

Fresh builds for Amazon Linux, Rocky Linux, Ubuntu, and Docker with every commit. 

Modern Integration

Your MTA no longer needs to be a black box. KumoMTA supports API injection/management, webhooks, AMQP, Kafka, secure keystores, and data-source-based configuration.

Automated Traffic Shaping

Automate your adherence to sending requirements. Thanks to our Lua-first configuration and automation design, you can adjust throttles, pause and resume traffic, and automate IP warmup. KumoMTA even supports rules on a per-tenant basis.

Cloud Friendly

With flexible deployment options, support for containers, clustered throttles, HAProxy and SOCK5 proxies, KumoMTA was built for those wanting to deploy in the cloud.

Complete Control

KumoMTA is designed around the belief that the user should have control of all decisions, with very little assumption out of the box. Use our standards-based Lua scripting engine to make it your own.