Add Keila to Mailing Lists and Newsletters (#2820)

README.md

@@ -419,6 +419,7 @@ Mailing lists servers and mass mailing software - one message to many recipients
 - [Dada Mail](https://dadamailproject.com/) - Web-based list management system that can be used for announcement lists and/or discussion lists. ([Source Code](https://github.com/justingit/dada-mail)) `GPL-2.0` `Perl`
 - [HyperKitty](https://wiki.list.org/HyperKitty) - Open source Django application to provide a web interface to access GNU Mailman v3 archives. ([Demo](https://lists.mailman3.org/), [Source Code](https://gitlab.com/mailman/hyperkitty)) `GPL-3.0` `Python`
 - [Listmonk](https://listmonk.app/) - High performance, self-hosted newsletter and mailing list manager with a modern dashboard. ([Source Code](https://github.com/knadh/listmonk)) `AGPL-3.0` `Go`
+- [Keila](https://www.keila.io) - Self-hosted reliable and easy-to-use newsletter tool. Alternative to proprietary services like Mailchimp or Sendinblue. ([Demo](https://app.keila.io), [Source Code](https://github.com/pentacent/keila)) `AGPL-3.0` `Elixir`
 - [Mailman](https://www.gnu.org/software/mailman/) - The Gnu mailing list server. `GPL-3.0` `Python`
 - [Mailtrain](https://mailtrain.org/) - Self hosted newsletter application. ([Source Code](https://github.com/Mailtrain-org/mailtrain)) `GPL-3.0` `Nodejs`
 - [MailyHerald](https://mailyherald.org/) - Self-hosted Mailchimp alternative that you can easily integrate with your site. Helps you send and manage your application mailings. It supports email marketing and conducting the daily stream of notifications you send to your users. ([Source Code](https://github.com/Sology/maily_herald)) `LGPL-3.0` `Ruby`