Koha - Koha is the first free and open source software library automation package (ILS).

MightyCall - Virtual phone system that lets you run your business from anywhere.

Evergreen ILS - Evergreen - Open Source Library Software

Tiki Wiki CMS Groupware - Tiki Wiki CMS Groupware, also known as Tiki (or TikiWiki), is a full-featured, web-based, multilingual, all-in-one Free/Libre Open Source Software solution. Tiki can be used to create all kinds of web apps, portals, knowledge bases, intranets, etc.

VuFind - VuFind is a library resource portal designed and developed for libraries by libraries.

ImpressPages CMS - ImpressPages is a PHP framework with admin panel.