ioBroker - flexible and modular application for the IoT and Smarthome
Home-Assistant.io - Home Assistant is an open-source home automation platform running on Python 3.
openHAB - "empowering the smart home" - vendor and technology agnostic open source home automation
Domoticz - Domoticz is a lightweight Home Automation System
Google Home - Set up, manage, and control your Chromecast, Chromecast Audio and Google Home devices.
HomeGenie - HomeGenie, Home Automaton Server in the Internet Of Things era