MIWIFI by Xiaomi - Wifi router beta with a twist: you build it yourself
Home-Assistant.io - Home Assistant is an open-source home automation platform running on Python 3.
Wifi Porter - Connect guests to your network quickly
ioBroker - flexible and modular application for the IoT and Smarthome
Velop - Whole-home mesh Wi-Fi by Linksys
openHAB - "empowering the smart home" - vendor and technology agnostic open source home automation