Browse free open source Email software and projects for Linux below. Use the toggles on the left to filter open source Email software by OS, license, language, programming language, and project status.

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  • 1
    PHPMailer

    PHPMailer

    The classic email sending library for PHP

    PHPMailer – A full-featured email creation and transfer class for PHP. Support for UTF-8 content and 8bit, base64, binary, and quoted-printable encodings. SMTP authentication with LOGIN, PLAIN, CRAM-MD5, and XOAUTH2 mechanisms over SMTPS and SMTP+STARTTLS transports. Validates email addresses automatically. Many PHP developers need to send email from their code. The only PHP function that supports this directly is mail(). However, it does not provide any assistance for making use of popular features such as encryption, authentication, HTML messages, and attachments. Formatting email correctly is surprisingly difficult. There are myriad overlapping (and conflicting) standards, requiring tight adherence to horribly complicated formatting and encoding rules – the vast majority of code that you'll find online that uses the mail() function directly is just plain wrong, if not unsafe!
    Downloads: 114 This Week
    Last Update:
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  • 2
    MailHog

    MailHog

    Web and API based SMTP testing

    Inspired by MailCatcher, easier to install. Built with Go, MailHog runs without installation on multiple platforms. Run it from Docker Hub or using the provided Dockerfile. The SMTP server starts on port 1025, the HTTP server starts on port 8025, in-memory message storage. ESMTP server implementing RFC5321. Support for SMTP AUTH (RFC4954) and PIPELINING (RFC2920). Web interface to view messages (plain text, HTML or source). Supports RFC2047 encoded headers. Real-time updates using EventSource. Release messages to real SMTP servers. Chaos Monkey for failure testing. HTTP API to list, retrieve and delete messages. See APIv1 and APIv2 documentation for more information. HTTP basic authentication for MailHog UI and API. Multipart MIME support. Download individual MIME parts. In-memory message storage. MongoDB and file based storage for message persistence. Lightweight and portable. No installation required.
    Downloads: 41 This Week
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  • 3
    Open source DKIM library, MTA filter implementation and associated tools.
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    Downloads: 182 This Week
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  • 4
    Google Apps Manager

    Google Apps Manager

    Command line management for Google G Suite

    Google Apps Manager or GAM is a free and open source command line tool for Google G Suite Administrators that allows them to manage many aspects of their Google Apps Account quickly and easily. With GAM you can create and manage users, groups and domains; manage email, security and calendar settings; manage admins and organizations and many more. To use GAM Google Apps Business, Education, Partner or Government Edition is required.
    Downloads: 23 This Week
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  • 5
    Bamboo

    Bamboo

    Testable, composable, and adapter based Elixir email library

    Bamboo is part of the thoughtbot Elixir family of projects. Flexible and easy-to-use email for Elixir. Built-in support for popular mail delivery services. Bamboo ships with adapters for several popular mail delivery services, including Mandrill, Mailgun, and SendGrid. It's also quite easy to write your own delivery adapter if your platform isn't yet supported. Deliver emails in the background. Most of the time you don't want or need to wait for the email to send. Bamboo makes it easy with Mailer.deliver_later. A functional approach to mail delivery. Emails are created, manipulated, and sent using plain functions. This makes composition a breeze and fits naturally into your existing Elixir app. Unit test with ease. Bamboo separates email creation and email delivery allowing you to test by asserting against email fields without the need for special functions. Dead-simple integration tests. Bamboo provides helper functions to make integration testing easy and robust.
    Downloads: 10 This Week
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  • 6
    mail-parser

    mail-parser

    Fast and robust e-mail parsing library for Rust

    Stalwart Mail Parser is a high-performance Rust library designed for parsing and analyzing email messages. It efficiently handles complex MIME structures, supports various encodings, and is optimized for speed and robustness. The library is suitable for applications requiring detailed email processing and analysis.​
    Downloads: 7 This Week
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  • 7
    base64 RFC1113 Vanilla ANSI-C Code for a portable stand-alone file encode/decode utility. In 2001, I asked people to 'Help me break it!' Since then, 10+years later, the code remains unbroken and is in wide production use world-wide. It has been ported to all major architectures and been used as a template for ports to different computer and human languages. This is very mature and stable code. Although this comes from a project that was constrained by export controls and is used in secure systems, it is not security code per-se. I have therefore altered the 'Export Controls' category.
    Downloads: 14 This Week
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  • 8
    basE91 is an advanced method for encoding binary data as ASCII characters. It is similar to UUencode or base64, but is more efficient. The overhead produced by basE91 depends on the input data. It amounts at most to 23% and can range down to 14%.
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    Downloads: 50 This Week
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  • 9
    MailSlurper

    MailSlurper

    Local, web-based mail server application. Slurp mails into oblivion!

    MailSlurper is a small SMTP mail server that slurps mail into oblivion! MailSlurper is perfect for individual developers or small teams writing mail-enabled applications that wish to test email functionality without the risk or hassle of installing and configuring a full-blown email server. It's simple to use! Simply set up MailSlurper, configure your code and/or application server to send mail through the address where MailSlurper is running, and start sending emails! MailSlurper will capture those emails into a database for you to view at your leisure. The following are general instructions for compiling MailSlurper. Your details may vary a bit here and there. The below example is based on a Unix-style system, such as Ubuntu or OSX. Furthermore, for instructional purposes, it is assumed that your GOPATH is set to ~/code/go, and that you have a folder in your source directory called github.com. Your setup may vary.
    Downloads: 1 This Week
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  • 10

    Roundup Issue Tracker

    Simple-to-use/-install issue-tracking system: web, REST, email, CLI

    Roundup is a simple-to-use and -install issue-tracking system with command-line, web, REST, XML-RPC, and e-mail interfaces. It runs on python 2.7 or 3.6 or newer. Roundup has been deployed for: * bug tracking and TODO list management (the classic installation) * customer help desk support (with a wizard for the phone answerers, linking to networking, system and development issue trackers) * issue management for IETF working groups * sales lead tracking ...and so on. It's been designed with flexibility in mind - it's not just another bug tracker. Roundup ships with a *demo tracker* to play with - after you've unpacked the source, just run "python demo.py" and load up the URL it prints out! Get current development source from mercurial repo at: <https://sourceforge.net/p/roundup/code/ci/default/tarball?path=>
    Downloads: 7 This Week
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  • 11
    A C callback orientated parser library for card (vCard/vCal) objects, reentrant & stream orientated, handles line folding, automatic decoding of params and data
    Downloads: 3 This Week
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  • 12
    RFC 2425 defines a MIME Content-Type for Directory Information. This library contains necessary methods to parse information blocks arranged in such a manner.
    Downloads: 5 This Week
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  • 13
    This is a Program code editor and code brower with built-in analysis for C/C++ programs.
    Downloads: 4 This Week
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  • 14
    Mstone is a mail performance measurement system. It can simultaneously test SMTP, POP, IMAP, and some HTML based systems. It measures transaction latency in multiple stages, and graphs the combined results from multiple clients.
    Downloads: 1 This Week
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  • 15
    CRM114 is a Controllable Regex Mutilator and filter. It provides arbitrary stream filtering for antispam, adkiller proxies, syslog monitoring, etc. CRM114 has a structured, easily understood way to express regex-based filters, and a learn-by-example mod
    Downloads: 3 This Week
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  • 16
    Konfidi is a trust framework that uses topical trust values from a social network of authenticated people. When you receive an email from someone you do not know, but he/she is in the network, Konfidi will compute an inferred trust value for you.
    Downloads: 3 This Week
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  • 17

    Visual Synapse

    Moved to GitHub → https://github.com/yoctobyte/visualsynapse

    Moved to GitHub → https://github.com/yoctobyte/visualsynapse --- Visual Synapse are component wrappers around the Synapse tcp/ip libraries. It wraps a few common internet protocols, like HTTP, UDP, DNS, ICMP, TCP and SMTP to multi-threaded components that can be used with Delphi, Kylix, Freepascal and C++ Builder.
    Downloads: 3 This Week
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  • 18

    libquickmail

    C library for sending e-mail (with attachments) from C/C++

    C library intended to give C/C++ developers a quick and easy way to send e-mail from their applications. Supports multiple To/Cc/Bcc recipients and multiple attachments without size limitation. For the actual SMTP communication either libcurl can be used or the built in SMTP support. The library can also be used to just create a multipart MIME message body. Also comes with a command line application (quickmail) for sending mails (mutiple attachments supported) from command line or scripts. Cross-platform. Binary packages available for Windows (32-bit and 64-bit).
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    Downloads: 1 This Week
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  • 19
    FakeSMTPServer is a solution for testing web-based products that require a "unique" email address. Instead of being a "real" smtp server, this server forwards all email to a single email address, or can output them to the console instead.
    Downloads: 2 This Week
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  • 20

    email-checker-php-sdk

    PHP SDK to connect with Easy Email Verification API and validate email

    The Email Checker PHP SDK is part of the Easy Email Verification - URL Checker ecosystem, designed to help developers integrate real-time email verification into their PHP applications. It uses the Easy Email Verification API to validate if an email address is real, active, and safe to use. The SDK performs domain and MX record checks, SMTP validation, and detection of disposable or role-based addresses. It provides a lightweight and reliable cURL-based implementation that returns structured JSON responses. This project is officially maintained by Easy Email Verification Ltd. For technical documentation and API reference, visit https://www.easyemailverification.com
    Downloads: 2 This Week
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  • 21
    xstress is a SMTP mail server stress testing tool. xstress creates multiple connections (using threads) to the (configured) mail server and sends mails with varying subject, body, attachment and TO/FROM addresses.
    Downloads: 1 This Week
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  • 22
    Forpost is an embeddable, interpreted stack-based(Forth-like) language which has simple, compact and effective implementation in ANSI C. Main features: heterogeneous arrays, higher-order functions, program/data equivalence.
    Downloads: 1 This Week
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  • 23
    An open PHP-based framework for the Nabaztag™ (http://www.nabaztag.com/) electronic pet. Due to major changes on the Violet backend, OpenNab can no longer be connected to it but it still can be used as a standalone server to set your bunnies free !
    Downloads: 1 This Week
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  • 24
    Sieve is a mail filtering language standardized as RFC 3028 / RFC 5228 and its extensions. libSieve provides a simple, clean API for parsing and executing Sieve scripts. Code is on GitHub: http://github.com/sodabrew/libsieve
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    Downloads: 1 This Week
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  • 25
    This anonymous emailer script written in PHP is a free, opensource project designed to send EMails from anyone to anyone, with additional details such as Reply-To ,an anti-spam CAPTCHA and a WYSIWYG.
    Downloads: 0 This Week
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