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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 don't have one personally but I did some research into their hardware when making a DIY clone a few years ago: https://github.com/shanet/clearair
The EPA published a paper calibrating the sensors PurpleAir uses with their much more expensive sensors and found it was fairly close after applying a correction factor. https://github.com/shanet/ClearAir/blob/master/docs/PurpleAi...
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