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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.
The 2003 source release of Duke3D under GPL includes a ZIP file with Ken Silverman's Build engine and the same weird license. I don't know if the Duke code can be compiled without Ken's code. Ken writes on http://www.advsys.net/ken/buildsrc/default.htm that the custom license is to stroke his own ego. Why he didn't at one point switch to one of the many short GPL-compatible licenses such as MIT's is something only he and his ego can answer.
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