Mail GitHub Repositories (2026) · Open Source Tools

Mail and calendar for Linux and macOS. Gmail and IMAP accounts, Google Calendar, contacts, OpenPGP and S/MIME. GTK4 and libadwaita, written in Rust.

✉️ Composable all-in-one mail server.

+30,000 free and disposable email domains in a single list, validated against DNS every day.

Free, unlimited business email on your own domains, running entirely in your free Cloudflare account.

:love_letter: A beautiful, fast and fully open source mail client for Mac, Windows and Linux.

mailcow: dockerized - 🐮 + 🐋 = 💕

📮 A fully featured open source mail delivery platform for incoming & outgoing e-mail

Disposable webmail server (similar to Mailinator) with built in SMTP, POP3, RESTful servers; no DB required.

Bichon – A lightweight, high-performance Rust email archiver with WebUI

Emails at the heart of your business logic!

terminal mail client, mirror of https://git.meli-email.org/meli/meli.git https://crates.io/crates/meli

Create and validate signed URLs with a limited lifetime

Send a welcome notification to new users

:gear: GitHub Action for sending emails

MIME mail encoding and decoding package for Go

Create and validate signed URLs with a limited lifetime

Convert MJML to HTML using PHP

Apps made with Cogent Core

Collect everything about sent mails in your Filament app.

📮 Email queue extending NodeMailer with multi SMTP transports and horizontally scaled applications support