Courier Mail Server vs OpenSMTPD
Courier Mail Server
courier-mta.orgOpenSMTPD
opensmtpd.orgSide by side
| Figure | Courier Mail Server | OpenSMTPD |
|---|---|---|
| Price from | Free | Free |
| Free plan | Yes | Yes |
| Free trial | — | — |
| Open source | — | — |
| macOS | — | Yes |
| Linux | Yes | Yes |
| Self-hosted | Yes | Yes |
| Plans published | 1 | 1 |
| Spec score · Mail Server Software | 8.5 (#1) | 7.4 (#28) |
| Filtering | Integrated mail filtering supports administrator-installed external filters and recipient-specified rules through maildrop. | Mail filters can evaluate SMTP sessions at phases including connection, HELO/EHLO, sender, recipient, data, and commit. |
| Platforms | The source should compile on most Linux and BSD-based POSIX operating systems, and may compile on Solaris and AIX with additional tools. | The portable release lists OpenBSD, FreeBSD, NetBSD, DragonFlyBSD, Linux, SmartOS, and macOS; support depends on package maintainers providing regular development feedback. |
| Security | Courier supports STARTTLS and SSL for ESMTP, IMAP, POP3, and webmail; its ESMTP client can require a certificate signed by a trusted root CA. | Project goals include careful validity checks on network input and privilege separation to mitigate possible security bugs. |
| Support | The site lists an unmoderated courier-users mailing list for questions, bug reports, and comments, plus a separate read-only announcement list. | The project is volunteer-developed and is not backed by a commercial entity. |
Plans
In their own words
Courier Mail Server
Courier Mail Server has no write-up on Specifiction yet; its figures are above.