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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.
OpenWatcom is a very nice compiler and debugger. Another one is QB64.
With both of those you can make some really nice DOS programs. Which you can then run in bochs (not virtualized, but an emulator. Close enough :) ).
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