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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.
With that background, if you're comfortable with schematics and doing pcb layouts, open-source modules can be the cheapest way to go. Here is a link with a bunch of github repos. Some have gerber files, you can send off to somewhere like JLCPCB to have the panels and PCBs made. Minimum order is 5 I think.
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