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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've worked in LK (Little Kernel), which is the basis of the Android and WebOS boot loaders, but is also a reasonable stand-alone operating system, ThreadX, which is a very lightweight RTOS, and one or two others. These were all written in C, but it was also quite a few years ago, so I suspect a good chunk of the industry has moved to C++.
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