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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.
In lower C++ standards I would highly recommend including this as a header-only library: https://github.com/HowardHinnant/date. This was the basis for the new date/timezone functionality in C++20, so it's nearly identical and works down to C++11.
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