
Description: Mailu is an open-source mail server that focuses on security and ease of deployment. It is designed to run in containers like Docker and handles email delivery, filtering, webmail access, contacts/calendar features, and more.
Type: Open Source Test Automation Framework
Founded: 2011
Primary Use: Mobile app testing automation
Supported Platforms: iOS, Android, Windows

Description: Poste.io is an open-source newsletter service that allows users to easily create, send, and manage email newsletters. It has a simple drag-and-drop editor to design newsletter templates and customizable subscription forms to grow mailing lists.
Type: Cloud-based Test Automation Platform
Founded: 2015
Primary Use: Web, mobile, and API testing
Supported Platforms: Web, iOS, Android, API