The Cyrus IMAP server

The Cyrus IMAP server was developed by Carnegie Mellon University as a replacement for their Andrew Message System. Cyrus has a number of interesting properties as an IMAP server:

One message per file

Index and Cache files.

Safe concurrent access:

Local Customisation to Cyrus

We have made a number of modifications to Cyrus to meet local needs. These modifications full into four broad categories:

The patches are available here.

We also wrote a small, stateless, IMAP and POP proxy server. This was principally because the Murder software was still rather immature when we started this project in 2002 : it seems to have stabilised quite nicely in the intervening time. The Murder has the substantial advantage that it provides transparent support for shared mailfolders.

David Carter <>