Radicale : The Radicale Project is a complete CalDAV (calendar) and CardDAV (contact) server solution.
deepstream.io : A Scalable Server for Realtime Web Apps
Stores and syncs data in realtime
Built in node.js
Works for browsers, backend & mobile
Scales via clustering...
RoadRunner : RoadRunner is an open source (MIT licensed), high-performance PSR-7 PHP application server, load balancer and process manager. It supports service mod...
GraphQL : GraphQL is a query language for APIs and a runtime for fulfilling those queries with your existing data. GraphQL provides a complete and understandabl...
YunoHost : YunoHost is a server operating system aiming to make self-hosting accessible to everyone.
Baïkal offers ubiquitous and synchronized access to your calendars and address books over CalDAV and CardDAV. Baïkal implements the current IETF recommendation drafts of these industry standards for centralized calendar and address book collections.