These instructions are based on Debian 8.0 because it has to be based on something. Other Linux distributions will be similar in the broad ideas but may differ in the specifics. If you already have a preferred distro, use that (we assume you know how to use its package management system). If you don't already have a preferred distro, maybe consider using Debian.

First make sure you have a copy of the source. You can either fetch the latest source from git, or download one of our release tarballs.

Setting up dependencies

Required Build Dependencies

Building a basic Cyrus that can send and receive email: the minimum libraries required to build a functional cyrus-imapd.

Package Debian RedHat Notes
autoconf autoconf autoconf  
automake automake automake  
bison bison bison  
Cyrus SASL libsasl2-dev cyrus-sasl-devel  
flex flex flex  
gcc gcc gcc  
gperf gperf gperf  
jansson libjansson-dev jansson-devel  
libbsd libbsd-dev libbsd-devel  
libtool libtool libtool  
ICU libicu-dev libicu-devel version 55 or newer
uuid uuid-dev libuuid-devel  
openssl (Note about versions) libssl-dev openssl-devel  
pkgconfig pkg-config pkgconfig  
sqlite libsqlite3-dev sqlite-devel  

To install all dependencies from packages on Debian Jessie, use this:

sudo apt-get install git build-essential autoconf automake libtool \
    pkg-config bison flex libssl-dev libjansson-dev libxml2-dev \
    libsqlite3-dev libical-dev libsasl2-dev libpcre3-dev uuid-dev \
sudo apt-get -t jessie-backports install libxapian-dev

Build dependencies for additional functionality

The following dependencies enable additional functionality, help with code maintenance tasks or are required for building the documentation.

Developers only

The developer dependencies are required if you are building from git sources, have modified certain source files from the release tarball, or have configured with --enable-maintainer-mode in order to build a new package.

If you are building normally from a pure release tarball, then you don't need these dependencies. The files, these dependencies produce, have been pre-built and included in the release, and do not normally need to be re-built.

Package Debian RedHat Required Notes
perl-devel perl-dev perl-devel no Needed for building binary perl libraries, version 5+.
perl(ExtUtils::MakeMaker)     no Needed for building extensions to Perl.
perl(Pod::POM::View::Restructured)     no Needed to generate man pages. This has to be available to the system-wide perl interpreter, found by which.
python(GitPython)     no Needed for building the documentation.
python(Sphinx)     no Needed for building the documentation.
transfig transfig transfig no Also known as fig2dev, transfig is an artifact from the old days, and is only used for generation of a couple of png files in the legacy documentation (doc/legacy/murder.png and doc/legacy/netnews.png). One day it should be merged into the current documentation, cause then we can get rid of it: issues/1769.
valgrind valgrind valgrind no Performance and memory testing.
xxd vim-common vim-common no Needed for the _js.h files, for CalDAV and CardDAV support.

SASL Authentication

Package Debian RedHat Required Notes
Cyrus SASL Plain libsasl2-modules cyrus-sasl-plain yes/no Required to pass Cyrus IMAP's PLAIN authentication unit tests.
Cyrus SASL MD5 libsasl2-modules cyrus-sasl-md5 yes/no Required to pass Cyrus IMAP's DIGEST-MD5 authentication unit tests.
sasl binaries sasl2-bin sasl2-bin no Administration tools for managing SASL.
Kerberos libsasl2-modules-gssapi-mit krb5-devel yes/no Development headers required to enable Kerberos v5 authentication capabilities, also known as the authentication mechanism GSSAPI. Configure option: --with-krbimpl=mit.

Alternate database formats

Package Debian RedHat Required Notes
mysql or mariadb libmysqlclient-dev or libmariadb-dev mysql-devel or mariadb-devel yes/no MariaDB or MySQL development headers, required to allow Cyrus IMAP to use it as the backend for its databases. Configure options: --with-mysql, --with-mysql-incdir, --with-mysql-libdir.
postgresql postgresql-dev postgresql-devel yes/no PostgreSQL development headers, required to allow Cyrus IMAP to use it as the backend for its databases. Configure option: --with-pgsql.

CalDAV, CardDAV, or JMAP (httpd subsystem)

Package Debian RedHat Required Notes
libbrotli libbrotli-dev brotli-devel no It provides Brotli compression support for http communications (otherwise only deflate and gzip (optionally) would be available).
libchardet libchardet-dev libchardet-devel yes/no It is used by the JMAP module of httpd to detect the character set of untagged 8-bit headers. Without it, cyrus-imapd will not do character-set detection. If some piece of data has no character set coming in, it will have no character set. Required for JMAP, but otherwise is not needed.
libical libical-dev libical-devel yes It provides calendaring functionality for CalDAV, which can't be used without this lib. Version 3.0.0 or higher is required.
libxml libxml2-dev libxml2-devel yes A fundamental lib for all *DAV functionality.
nghttp2 libnghttp2-dev libnghttp2-devel no HTTP/2 support for the entire httpd subsystem (*DAV & JMAP).
shapelib shapelib shapelib yes/no It is required for tzdist service to have geolocation support. Otherwise it is not needed. Version 1.3.0 or higher is required when using it.
wslay libwslay-dev wslay-devel no It provides WebSockets support in httpd. Only used with JMAP, otherwise not needed. Version 1.1.1 or higher is required when using it.
zlib zlib1g-dev zlib-devel no It provides gzip compression support for http communications.


Package Debian RedHat Required Notes
CUnit libcunit1-dev cunit-devel no Development headers for compiling Cyrus IMAP's unit tests. Required to run make check.
SSL certificates ssl-cert-dev mod_ssl no Used if you're installing SSL certificates.
ClamAV libclamav-dev clamav-devel no It is used by cyr_virusscan, otherwise not needed.
CLD2 libcld2-dev cld2-devel yes/no Compact Language Detector 2 (probabilistically detects over 80 languages in Unicode UTF-8 text, either plain text or HTML/XML). Required for Xapian (--enable-xapian), otherwise not needed.
openldap libldap2-dev openldap-devel no Development headers to enable ptloader to interface with LDAP directly, for canonification of login usernames to mailbox names, and verification of login usernames, ACL subjects and group membership. Configure option: --with-ldap.
pcre libpcre3-dev pcre-devel yes PCRE 1 (8.x) - for utf-8/unicode regular expression matching. Could be replaced by something else in the future. See issues/1731 for more information.
perl(Term::ReadLine)     no Perl library needed by cyradm.
libsrs2 no package no package no It is used for implementing Sender Rewriting Scheme (SRS) functionality for messages forwarded by sieve scripts. Without it, messages forwarded by sieve scripts will not have this functionality and might have difficulty delivering to SMTP servers that insist on it.
Install tools for building
  • sudo apt-get install build-essential
Optionally install dependencies for building the docs.
  • sudo pip install python-sphinx
  • sudo cpan install Pod::POM::View::Restructured

Compile Cyrus

There are additional compile and installation steps if you are using Xapian for searching, or if you are using jmap.

Default build: mail only

$ autoreconf -i
$ ./configure [options]

Check the summary after ./configure completes to ensure it matches your expectations.

To view all options, and disable or enable specific features, please see:

# ./configure --help


Passing environment variables as an argument to configure, rather than setting them in the environment before running configure, allows their values to be logged in config.log. This is useful for diagnosing problems.

Optional dependencies

Some features are disabled by default and must be explicitly enabled via configure.

Sieve is enabled by default.


./configure --enable-http --enable-calalarmd --enable-jmap


./configure --enable-murder


./configure --enable-replication


cd /path/to/cyrus-imapd

autoreconf -i -s   # generates a configure script, and its various dependencies

./configure CFLAGS="-W -Wno-unused-parameter -g -O0 -Wall -Wextra -Werror -fPIC" \
--enable-coverage --enable-calalarmd --enable-autocreate \
--enable-nntp --enable-http --enable-unit-tests \
--enable-replication --with-openssl=yes --enable-murder \
--enable-idled --prefix=/usr/cyrus

make lex-fix   # you need this if compile fails with errors from sieve/sieve.c


The --prefix option sets where Cyrus is installed to.

It may be of use to also add --std=gnu99 to the CFLAGS. That generates TONS of warnings.

Having problems with compilation or linking?

If you're running on Debian, and you install to /usr/local, you may need to update your library loader. Edit /etc/ so it includes the following additional line:


Without this, when you attempt to start Cyrus, it reports error while loading shared libraries: cannot open shared object file: No such file or directory because it can't find the Cyrus library in /usr/local/lib.


make check    # this runs the cunit tests.

This runs the cunit tests and is used for testing that the libraries support all the expected behaviour. If this fails, please report it to the cyrus-dev mailing list with details of your source version, operating system and affected libraries.

Next: installing Cyrus.