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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.
They still are open source [1].
If I had to guess, the reason they locked the bootloader is the same reason they removed the symbolic math functionality (which is re-added in Omega [2]), test accreditation.
They want to create a calculator to provide a good and viable alternative to TI. They can only do that if their calculator is allowed on tests like the ACT, SAT, etc.
[1]: https://github.com/numworks/epsilon
NOTE:
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