Anubis is a daemon that sits between the Mail User Agent (MUA) and the Mail Transfer Agent (MTA). When a mail is sent by a user in the MUA, it is first passed to Anubis, which performs additional processing to the message before passing it on for delivery by the MTA. Anubis may, for example, modify the message headers or body, or encrypt or sign the message.

This is an address lookup tool using a Notmuch database, useful for email address completion.

smtpmail is a little console-based tool for users who have no local mailserver on their machine. It enables these users to send their mail over a remote SMTP server.

Mail::SPF is the Sender Policy Framework implemented in Perl.

bower is a curses front-end for the Notmuch email system, written in the Mercury language.

Sieve-connect lets you view, upload, edit, delete, and otherwise manage Sieve scripts on any mail server that speaks the ManageSieve protocol, as specified in RFC 5804.

Sieve (RFC 5228) is a specialised language for e-mail filtering. Sieve scripts are stored on the server and run whenever mail arrives. They can automatically sort new messages into folders, silently reject them, send an automated response, and more.

sieve-connect is designed to be both a tool which can be invoked from scripts as well as a decent interactive client. It supports TLS for connection privacy, as well as authentication with SASL or GSSAPI client certificates. It should be a drop-in replacement for sieveshell from the Cyrus IMAP project.

A flexible, extensible mail retrieval system with support for POP3, IMAP4, SSL variants of both, maildirs, mboxrd files, external MDAs, arbitrary message filtering, single-user and domain-mailboxes, and many other useful features. This is a fork derived from getmail 5.14, aimed at Python 3 compatibility.

CRM114 is a system to examine incoming e-mail, system log streams, data files or other data streams, and to sort, filter, or alter the incoming files or data streams according to the user's wildest desires. Criteria for categorization of data can be via a host of methods, including regexes, approximate regexes, a Hidden Markov Model, Orthogonal Sparse Bigrams, WINNOW, Correlation, KNN/Hyperspace, or Bit Entropy (or by other means--it's all programmable).

Urlscan is a small program that is designed to integrate with the Mutt mail reader to allow you to easily launch a Web browser for URLs contained in email messages. It parses an email message or file and scans it for URLs and email addresses. It then displays the URLs and their context within the message, and allows you to choose one or more URLs to send to your Web browser. Alternatively, it send a list of all URLs to standard output. It is a replacement for the urlview program.

libESMTP is an SMTP client that manages posting (or submission of) electronic mail via a preconfigured MTA.

It may be used as part of a MUA, or other program that must be able to post electronic mail where mail functionality may not be that program's primary purpose.

libESMTP's high-level API shields developers from the complexity of SMTP. It transparently handles many SMTP extensions including authentication, TLS, and PIPELINING for performance. Even without a pipelining server, libESMTP offers much better performance than would be expected from a simple client.

This package provides tools for the conversion of Outlook Express data files to standard mailbox format.

The hyperkitty Django app provides a web user interface to access GNU Mailman3 archives, and manage it. This interface uses django, and requires some configuration.

Email::Address::XS implements RFC 5322 parser and formatter of email addresses and groups. Unlike Email::Address, this module does not use regular expressions for parsing but instead is implemented in XS and uses shared code from Dovecot IMAP server.

Esmtp is a simple relay-only mail transfer agent built using libESMTP. It sends e-mail via a remote SMTP server using credentials from the user's $HOME/.esmtprc configuration file; see the esmtprc man page for more on configuration. This package also provides minimal compatibility shims for the sendmail, mailq, and newaliases commands.

This package contains libraries and templates for Django-based interfaces interacting with Mailman.

TNEF is a tar-like program that unpacks MIME attachments of type application/ms-tnef.

ripMIME is a small program to extract the attached files out of a MIME-encoded email package.

Nullmailer is a simple replacement MTA for hosts that receive no local mail and only relay mail to a fixed set of smart relays. It's useful for systems such as Web servers that must be able to send email notifications, without having to run a full-blown MTA such as sendmail or qmail.

Nullmailer is designed to be simple to configure, easy to extend, and secure. It requires little ongoing administration. The included sendmail emulator front-end should allow most (if not all) sendmail-compatible programs to run without any changes.

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

Abook is a text-based address book program designed to use with the Mutt mail client.

GMime provides a core library and set of utilities which may be used for the creation and parsing of messages using the Multipurpose Internet Mail Extension (MIME).

Email::Simple provides simple parsing of RFC 2822 message format and headers.

The filter-rspamd OpenSMTPd filter implements the Rspamd protocol and allows OpenSMTPd to request an Rspamd analysis of an SMTP transaction before a message is committed to queue.

The Libpst utilities include readpst which can convert email messages to both mbox and MH mailbox formats, pst2ldif which can convert the contacts to .ldif format for import into LDAP databases, and other tools to process Outlook email archives.