Citadel
Citadel is an innovative platform that enables seamless email, collaboration, groupware, and content management tailored for both local hardware and cloud environments. I... Citadel is an innovative platform that enables seamless email, collaboration, groupware, and content management tailored for both local hardware and cloud environments. Its unique room-based architecture offers intuitive organization, making it user-friendly and adaptable. As 100% open source software under the GNU General Public License, it delivers powerful features without restrictions or costly enterprise limitations.
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