EarnIn Senior Software Developer interview questions

Design architecture to drive a dashboard We want to track the temperature in ~ a million sites around the US, and alert when a location heats up over a certain limit. Measurement is done by IOT devices connected to the internet. They each make one reading every second Communication to/from the devices can occasionally break If we encounter reading miss, we skip them If a device misses 5 readings in a row, we assume it is offline. Real time value is a moving average of the last 5 reading We want the dashboard to work reasonably close to real time. Display, with the ability to dive in: (*) Locations where temperature is over limit. Order by urgency Dive in: Temprature in the past 24 hours. Dive further: Temperature trends in location iin the past 3 months, 10 minutes samples (*) Number of devices online and in total Dive in: list of locations/device. Dive further: Temprature in the past 24 hours. Dive further: Temperature trends in location iin the past 3 months, 10 minutes samples

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