-
InfluxDB
Power Real-Time Data Analytics at Scale. Get real-time insights from all types of time series data with InfluxDB. Ingest, query, and analyze billions of data points in real-time with unbounded cardinality.
I used open hab https://www.openhab.org/ for a while and really liked it but had trouble getting it to work with the ZigBee USB stick I bought. So I switched to home assistant and have been on that for a couple years now. Both are solid. I like HA a lot but the one down side for me is I have to pay the 5 bucks a month or whatever it is for the cloud access to control things when I'm not home. Openhab has instructions to set up your own server for remote access.
NOTE:
The number of mentions on this list indicates mentions on common posts plus user suggested alternatives.
Hence, a higher number means a more popular project.