Postfix alternatives and similar software solutions

Based on the "Mail Transfer Agents" category.

Postal

9.2 6.1 Postfix VS Postal

📮 A fully featured open source mail delivery platform for incoming & outgoing e-mail
MailHog

9.1 0.0 Postfix VS MailHog

Web and API based SMTP testing

Stop vibe-debugging. Every exception, every backtrace, grouped so you see patterns, not noise.

Promo www.appsignal.com

MailCatcher

8.0 7.9 L5 Postfix VS MailCatcher

Catches mail and serves it through a dream.
Haraka

7.9 8.4 L3 Postfix VS Haraka

A fast, highly extensible, and event driven SMTP server
Maildrop

5.5 0.0 Postfix VS Maildrop

DISCONTINUED. Disposable email SMTP server, also useful for development.
Exim

5.2 9.6 L1 Postfix VS Exim

DISCONTINUED. Exim Mail Transport Agent - source, testsuite and documentation
OpenSMTPD

4.7 8.4 L2 Postfix VS OpenSMTPD

This is official OpenSMTPD Portable repository. Forks, pull requests and other contributions are welcome!
Slimta

2.9 2.8 L5 Postfix VS Slimta

Python libraries to send, receive, and queue email.
Courier MTA

2.2 8.3 L1 Postfix VS Courier MTA

Courier Mail Server
Lightmeter

1.0 0.0 Postfix VS Lightmeter

Lightmeter uses GitLab, not GitHub -- find repos at: https://gitlab.com/lightmeter
Qmail

1.0 0.0 Postfix VS Qmail

Bind to different local ip addresses depending on the domain part of the sender argument when using `qmail-remote`.
chasquid

- Postfix VS chasquid

SMTP
Sendmail

- Postfix VS Sendmail

Message transfer agent