Open Source Home Automation
Home automation that routes through a vendor's cloud stops working the day the company folds or the servers blink out - lights that need the internet to turn on are a downgrade from a dumb switch. So local control is the whole question, and the open source hubs below answer it by running on a box in your house, talking to devices over local protocols, and keeping your routines and sensor history on hardware you own, so your home keeps responding even when your connection or the manufacturer doesn't.
Home Assistant
Open source home automation with local control and privacy first
Homebridge
Lightweight Node.js server that adds HomeKit support to non-HomeKit smart home devices
Node-RED
Low-code flow editor for event-driven applications with a large library of nodes and flows
ESPHome
Turn ESP32, ESP8266, BK72xx, and RP2040 devices into smart home devices from configuration files
Domoticz
Free open source home automation system for monitoring and controlling lights, switches, and sensors
Gladys Assistant
Privacy-first open-source smart home assistant for local automation and device control
ioBroker
Open source IoT platform for home automation, data logging, and system integration on premise
openHAB
Vendor- and technology-agnostic open source home automation software