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Postal — open source alternative

Self-hosted mail server for sending transactional and bulk email.

Strengths

  • Web UI, SMTP and HTTP API out of the box.
  • Per-server tracking (opens, clicks, bounces).
  • Modular MariaDB + RabbitMQ architecture.

Weaknesses

  • Running a real mail server is a deliverability project, not an install.
  • IP warm-up and SPF/DKIM/DMARC on you.
  • Many cloud providers block outbound :25 entirely.
License: MIT Self-host difficulty: 4/5 Self-host only

Official site · Source on GitHub

Ad slot — OSS middle

Postal is used as an alternative to

SendGrid

Transactional email API for apps, now Twilio SendGrid.

See all alternatives →

Mailgun

Developer-focused transactional email and SMTP relay.

See all alternatives →

More open source in this category

Discover other projects tagged Transactional Email on the category page.

Other open source projects in Transactional Email

Haraka

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

License: MIT

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