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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.
Not and robotics/electronics, but I've an open source project CommandHunt which uses java spring-boot and react. It's very simple to learn and you can contribute to it. Start with fixing some sonar issues and you will get good understanding of the how a web application works.
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