[LAU] OT: Amazon Lab 126 and Linux

I just came across this job posting https://www.amazon.jobs/en/jobs/894336/applied-scientist from Amazon Lab 126 and am positively surprised that they are asking for experience with Alsa, Linux and realtime systems. Lab 126 seems to be an R&D lab contributing to products like Kindle, Fire tablets, Fire TV and Amazon Echo, the speaker for their Alexa service which suffers from severe privacy issues, see https://en.wikipedia.org/wiki/Amazon_Alexa#Privacy_concerns Does anyone know if any of these devices are using Linux as their OS? A quick online research did not confirm nor deny this. Despite Echo/Alexa being a questionable product in my view, as for example described in https://www.engadget.com/2019/04/30/hey-alexa-how-can-we-escape-surveillanc… it would be a great example of widespread use of Linux in an audio product.