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Haraka — open source alternative

High-performance Node.js SMTP server used by big senders.

Strengths

  • Plugin-based — you shape the flow in JavaScript.
  • Async core handles high connection counts.
  • Runs outbound relay and inbound MX workloads.

Weaknesses

  • Not a batteries-included product — you build on top.
  • Documentation assumes SMTP fluency.
  • No baked-in UI for campaign management.
License: MIT Self-host difficulty: 4/5 Self-host only

Official site · Source on GitHub

Ad slot — OSS middle

Haraka is used as an alternative to

Mailgun

Developer-focused transactional email and SMTP relay.

See all alternatives →

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