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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.
It isn't 100% MRI 3.0 compatible[0] and wasn't able to run Rails at first. It's also not always faster for Rails which occupies a lot of Ruby mindshare.
[0] https://github.com/oracle/truffleruby#current-status
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