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...
Fluid Framework : Fluid Framework is a collection of client libraries for building distributed, real-time collaborative web applications. These libraries allow multiple...
New Relic : New Relic’s SaaS-based Application Performance Monitoring helps you build, deploy, and maintain great web software.
Also, server monitoring, and more.
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.