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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.
Look at https://github.com/gnuless/ncc .. the libc there is not complete, but pretty substantial. Most of stdio is there. It's been pieced together from the Minix/ACK libc, Coherent, BSD sources. Should be enough to see how a standard library is put together.
I was going to recommend Musl, but since it was mentioned, maybe Sortix's Libc? it is directed to Sortix and will not work without any adaptation in Linux, but it is very well written and can give you some insight into how things work/are implemented.
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