# OpenSMTPD

9 Hacker News commenters recommended OpenSMTPD and 4 criticized it, November 2025 to November 2026. It was recommended in 3 of 13 months.

**Verdict:** Recommended as a simple, low-config mail server that runs well on small OpenBSD and Linux machines. Critics cite its security record, including a past remote root vulnerability.

## Why people recommend it

- Simple, minimal configuration (3 comments): "no nonsense and configuration feels rather modern compared to the legacy stuff that's out there" ([source](https://news.ycombinator.com/item?id=48196388)) "runs out of the box with minimal config on very low ram kvms" ([source](https://news.ycombinator.com/item?id=48198069)) "OpenSMTPD is also an absolute breeze" ([source](https://news.ycombinator.com/item?id=49143161))
- Happy long-term use (2 comments): "I'm happy with it. Been running OpenSMTPd for many years at this point, on both OpenBSD and Linux, and I have no complaints." ([source](https://news.ycombinator.com/item?id=48196865)) "now happily running OpenSMTPd" ([source](https://news.ycombinator.com/item?id=46757629))
- Default choice for simple mail (2 comments): "when I need a simple MTA (which is to say, in almost all cases)" ([source](https://news.ycombinator.com/item?id=48198668)) "It is the best SMTP server for the majority of use cases." ([source](https://news.ycombinator.com/item?id=48197724))

## What people warn about

- Past security vulnerabilities and CVEs (3 comments): "if you look at the security track record of opensmtpd, you'll quickly see" ([source](https://news.ycombinator.com/item?id=50121690)) "their SMTP server had a remote root RCE a few years ago" ([source](https://news.ycombinator.com/item?id=50121220)) "where opensmptd hasn't (CVE-2020-7247)" ([source](https://news.ycombinator.com/item?id=48336090))

## Alternatives hackers recommend

- [Stalwart Mail Server](https://hackerapproved.com/p/stalwart-mail-server.md): 27 recommend
- [Postfix](https://hackerapproved.com/p/postfix.md): 21 recommend
- [Dovecot](https://hackerapproved.com/p/dovecot.md): 18 recommend
- [qmail](https://hackerapproved.com/p/qmail.md): 15 recommend
- [mailcow](https://hackerapproved.com/p/mailcow.md): 15 recommend

## Cite as

Hacker Approved, "OpenSMTPD", https://hackerapproved.com/p/opensmtpd/ (counts from 1,795,640 Hacker News comments, November 2025 to November 2026).