KumoMTA is architected for the performance needed by enterprise senders, with support for technologies including webhooks, AMQP, Kafka, Vault, Prometheus, Grafana, and direct database access.

KumoMTA is the best choice for high-volume senders who want to be free from the restrictive commercial licensing provided by commercial MTAs, or who want the speed and flexibility not provided by other Open-Source MTAs.

We've been using Kumo MTA for six months now, and it's hands-down the best MTA out there. It's open-source, super customizable, and insanely high-performance. Plus, it's very stable and comes with complete and clear documentation. The team behind Kumo knows their stuff—everything about it is well-designed and can handle pretty much any email situation from a simple single-tenant installation sending a few thousand transactional emails a month to large scale distributed multi-tenant ESPs with complex shaping, sending and throttling rules sending millions of messages a day.

Perfect MTA to deliver millions of emails

Kumo? Only the best damn MTA - ever.

KumoMTA

Fast & Flexible Open-Source High-Volume Email Infrastructure

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