The purpose of this mail library is to provide a portable, efficient framework for different kinds of mail access: IMAP, SMTP, POP and NNTP. It provides an API for C language. It's the low-level API used by MailCore and MailCore 2.

Dovecot is a mail server whose major goals are security and reliability. It supports mbox/Maildir and its own dbox/mdbox formats.

Pigeonhole adds support for the Sieve language (RFC 5228) and the ManageSieve protocol (RFC 5804) to the Dovecot e-mail server.

Sieve is a language for filtering incoming mail. Messages can be forwarded or sorted into separate folders. Unwanted messages can be rejected or discarded, and, when the user is not available, the Sieve interpreter can send an automated reply.

Sieve is meant to be simple, extensible, and system-independent. The intention is to make it impossible to write anything more complex (and dangerous) than simple mail filters. Unlike most other mail filtering script languages, Sieve does not allow users to execute arbitrary programmes.

Through the ManageSieve protocol, users can remotely manage their Sieve scripts without needing file system access. The server accepts only valid scripts to prevent embarrassing errors later on.

NeoMutt is a command-line mail reader which is based on Mutt. It adds a large amount of new and improved features to Mutt.

Notmuch is a command-line based program for indexing, searching, read- ing, and tagging large collections of email messages.

Sendmail is a mail transfer agent (MTA) originally developed by Eric Allman. It is highly configurable and supports many delivery methods and many transfer protocols.

This package provides a TNEF stream reader library and related tools to process winmail.dat files.

Email::Sender replaces the old and sometimes problematic Email::Send library.

This project is a reimplementation of the Python stdlib smtpd.py based on asyncio.

pan is a Usenet newsreader that's good at both text and binaries. It supports offline reading, scoring and killfiles, yEnc, NZB, PGP handling, multiple servers, and secure connections.

dovecot-libsodium-plugin provides a libsodium password hashing scheme (such as scrypt) plug-in for Dovecot.

IMAPFilter is a mail filtering utility. It connects to remote mail servers using IMAP, sends searching queries to the server and processes mailboxes based on the results. It can be used to delete, copy, move, flag, etc. messages residing in mailboxes at the same or different mail servers. The 4rev1 and 4 versions of IMAP are supported.

Swaks is a flexible, scriptable, transaction-oriented SMTP test tool. It handles SMTP features and extensions such as TLS, authentication, and pipelining; multiple versions of the SMTP protocol including SMTP, ESMTP, and LMTP; and multiple transport methods including unix-domain sockets, internet-domain sockets, and pipes to spawned processes. Options can be specified in environment variables, configuration files, and the command line allowing maximum configurability and ease of use for operators and scripters.

Fetchmail is a full-featured, robust, well-documented remote-mail retrieval and forwarding utility intended to be used over on-demand TCP/IP links (such as SLIP or PPP connections). It supports every remote-mail protocol now in use on the Internet: POP2, POP3, RPOP, APOP, KPOP, all flavors of IMAP, ETRN, and ODMR. It can even support IPv6 and IPSEC.

Fetchmail retrieves mail from remote mail servers and forwards it via SMTP, so it can then be read by normal mail user agents such as mutt, elm or BSD Mail. It allows all your system MTA's filtering, forwarding, and aliasing facilities to work just as they would on normal mail.

msmtp is an SMTP client. In the default mode, it transmits a mail to an SMTP server (for example at a free mail provider) which takes care of further delivery.

Muchsync brings Notmuch to all of your computers by synchronizing your mail messages and Notmuch tags across machines. The protocol is heavily pipelined to work efficiently over high-latency networks such as mobile broadband. Muchsync supports arbitrary pairwise synchronization among replicas. A version-vector-based algorithm allows it to exchange only the minimum information necessary to bring replicas up to date regardless of which pairs have previously synchronized.

public-inbox implements the sharing of an email inbox via Git to complement or replace traditional mailing lists. Readers may read via NNTP, IMAP, Atom feeds or HTML archives.

This package provides Python bindings to use the Notmuch mail indexing and search library.

This package provides a tool to extract, recover and undelete email messages from Outlook Express .dbx files.

Postorius is a Django app which provides a web user interface to access GNU Mailman.

Mail::DKIM is a Perl module that implements the DKIM standard, and the older Yahoo! DomainKeys standard, both of which sign and verify emails using digital signatures and DNS records. Mail-DKIM can be used by any Perl program that wants to provide support for DKIM and/or DomainKeys.

Mairix is a program for indexing and searching email messages stored in Maildir, MH, MMDF or mbox folders.

GNU Mailutils is a collection of programs for managing, viewing and processing electronic mail. It contains both utilities and server daemons and all operate in a protocol-agnostic way. The underlying libraries are also available, simplifying the addition of mail capabilities to new software. GNU Mailutils provides the following commands:

• dotlock

• decodemail

• frm

• from

• guimb

• mail

• mailutils

• mailutils-config

• messages

• mimeview

• movemail

• popauth

• putmail

• readmsg

• sieve

bubger is a mailing list archive generator for mail stored in IMAP. It produces static files of HTML, Atom and mboxrd, making its output easy to serve from a host without IMAP access. It requires the IMAP THREAD extension.