Firebase - Firebase is a cloud service designed to power real-time, collaborative applications for mobile and web.
Openfire - Openfire (formerly Wildfire) is a cross-platform instant messaging (IM) and groupchat server.
Flatfile - The new standard for data import
Apache Vysper - Apache Vysper aims to be a modular, full featured XMPP (Jabber) server.
Blazor - An experimental web UI framework using C#/Razor and HTML, running in the browser via WebAssembly
Matrix.org - Matrix is an open standard for decentralized persistent communication over IP.