News•Mar 31, 2026
We Migrated Our Email Infrastructure to KumoMTA. Here's Why It Matters for You.
Postmark has completed a full migration from the proprietary PowerMTA platform to KumoMTA, an open‑source, Rust‑based mail transfer agent. The new engine cuts average queue times by roughly 30‑40% for Gmail, Yahoo, Microsoft and Apple, while bounce rates stay flat. KumoMTA’s real‑time traffic shaping, webhook observability and cloud‑native auto‑scaling give Postmark finer control over deliverability. The upgrade lays a scalable foundation for future feature development and resilience against mailbox‑provider throttling.
