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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 think the 6502 and Z80 processors would be good options. It seems like both have good supporting communities, and you can source the parts easily (and they're not crazy expensive). If you end up going with the 6502, Ben Eater's video series is helpful. I would expect there are similar video series out there for Z80.
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