Private email infrastructure & deliverability engineering
northboundmail.net
NorthboundMail Systems
Est. 2011 — SMTP infrastructure & deliverability
Infrastructure

Postfix

Hardened Postfix installations for API-driven, transactional and general-purpose outbound email. Configured, monitored and operated by engineers who have run Postfix in production since the mid-2000s.

Overview

Postfix is a mature, well-understood MTA that fits many sending profiles better than PowerMTA. For transactional traffic, per-user notifications, low-to-medium marketing volumes, and general outbound relay, Postfix delivers the same inbox placement at lower cost and complexity.

Northbound operates Postfix installations with the same discipline we apply to PowerMTA: version-controlled config, monitored queues, rotated DKIM keys, feedback loop routing, and per-transport tuning where it matters.

Benefits

  • Open-source, well-audited, no license overhead
  • Fits transactional and API-driven traffic patterns
  • Simple to reason about; fewer knobs to misconfigure
  • Excellent Postfix-native TLS and SASL support

Technical specifications

Postfix version3.7+ on hardened Linux
SigningOpenDKIM with per-sender key selection
Queue managementPer-transport pinning, custom back-off

Use cases

  • — Transactional senders: receipts, password resets, notifications
  • — SaaS platforms sending per-tenant notifications
  • — Internal relays for corporate email

Questions

When would we choose Postfix over PowerMTA?
When per-VMTA policy and PowerMTA's specific accounting are not required, Postfix offers a simpler operational surface at a much lower cost.

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