Xandikos

Lightweight CalDAV/CardDAV server on top of Git.

5 Alternatives To Xandikos

FileAgo

Secure file storage and collaboration solution for teams

HRCloud2

A full-featured home-hosted Cloud Drive & Personal Assistant.

Radicale

The Radicale Project is a complete CalDAV (calendar) and CardDAV (contact) server solution.

SOGo

SOGo is groupware server with a focus on scalability and open standards.

ownCloud

ownCloud is an open source project enabling businesses to host their own cloud storage while maintaining regulatory and compliance needs.