Top pick · highest health
Dovecot
IMAP and POP3 server written primarily with security in mind.
★ 1.3k 1223 commits / 90d ⟳ yesterday MIT
Category
Open source communication - email - mail delivery agents
Mail Delivery Agents (MDAs) - IMAP/POP3 server software. This page ranks 3 open-source mail delivery agents projects by a health score recomputed every night from repository data; nothing else affects the order. Dovecot leads at 82/100 with 1,223 commits in the last 90 days and 1.3k stars, followed by Cyrus IMAP (81) and DavMail (57). 2 of the 3 score 70 or above, 0 publish a Docker image, and the median health is 81. MIT is the most common licence, carried by 1 of them. The score weighs commits in the last 90 days, release recency, stars, archive status and Docker support; a low number means low measurable activity, not low quality, so a finished, stable tool can legitimately sit lower down.
updated Oct 2026 3 tools ★ 2.7k stars 0 with Docker median 81
Best for…
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Most starred
1,273 stars on GitHub, the largest community in the category.
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Most active
1,330 commits in the last 90 days, the fastest-moving codebase here.
Ranked by health
Table view
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Cyrus IMAP
Email (IMAP/POP3), contacts and calendar server.
★ 652 1330 commits / 90d ⟳ yesterday BSD-3-Clause-Attribution
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DavMail
POP/IMAP/SMTP/Caldav/Carddav/LDAP exchange gateway allowing users to use any mail/calendar client with an Exchange server, even from the internet or behind a firewall through Outlook Web Access.
★ 774 300 commits / 90d ⟳ yesterday GPL-2.0
| # | ||||||
|---|---|---|---|---|---|---|
| 1 | Dovecot | 1.3k | 1223 | MIT | yesterday | |
| 2 | Cyrus IMAP | 652 | 1330 | BSD-3-Clause-Attribution | yesterday | |
| 3 | DavMail | 774 | 300 | GPL-2.0 | yesterday |
How the mail delivery agent tools compare
Dovecot edges Cyrus IMAP 82 to 81, and most of the difference is stars: 1.3k stars against 652 stars. Cyrus IMAP is the busier codebase, though, with 1,330 commits in 90 days to 1,223.
The most recent release is Cyrus IMAP cyrus-imapd-3.12.4, published 2 months ago. DavMail publishes no tagged releases, which costs up to 25 of the 100 points. None of the measured options scores under 40. By stack, C (2) and Java (1) are the most common. Dovecot and Cyrus IMAP are permissively licensed; DavMail is copyleft.
Communication - Email - Mail Delivery Agents: common questions
What is the best open source mail delivery agent tool?
By Repoly's GitHub health score, Dovecot at 82/100 (1,223 commits in 90 days, 2.4.5 from 2 months ago). Cyrus IMAP is next at 81; Dovecot's lead comes mostly from stars. The score measures maintenance, not features, so shortlist the top few and try them.
Which mail delivery agent tools are the most actively developed?
Cyrus IMAP (1,330 commits in 90 days), Dovecot (1,223 commits in 90 days) and DavMail (300 commits in 90 days). Commit activity is 35 of the 100 health points, the largest single term.
Which mail delivery agent tools can I run in Docker?
None of the 3 advertise Docker support, so plan for a native install.
Which mail delivery agent tools have a permissive licence?
2 of 3: Dovecot (MIT), Cyrus IMAP (BSD-3-Clause-Attribution). 1 are copyleft.