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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 love Open Library (and the internet archive project in general)—I've read so many good books through them! I really hope they don't get shut down.
They're also truly open source: https://github.com/internetarchive/openlibrary/
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