Hybrid & Custom Infrastructure

For "admirals" who build their own fleet. This section covers "hybrid" setups where a company might use its own MTAs (like PowerMTA) for sending but integrate with a cloud ESP for content and analytics. This is the expert-level, high-control setup.

12 questions in this topic

What is hybrid sending (ESP + custom MTA)? Why do some companies build their own mail servers? What are the benefits and risks of self-hosting email infrastructure? What’s the difference between Postfix, Exim, and PowerMTA? What is a “deliverability cluster”? How to integrate custom routing with ESP tracking? How do hybrid setups handle authentication? How do internal relay chains affect traceability? What’s the advantage of on-premise logs? How to prevent custom servers from becoming open relays? What is message queuing middleware (RabbitMQ, Kafka) in email pipelines? When does hybrid make sense vs commercial ESP?

Questions about Hybrid & Custom Infrastructure