After applying it took around one week before I was sent a hackerrank test. I passed the test, despite that for at least two questions the correct answer was missing in the list of possible answers (hint to test creators: standard deviation is not the same as variance, and you may also want to check the function output space in questions 2; moreover, if you copy leetcode questions and modify them, don't forget to also modify the test conditions). Next was a 1 hour "interview". The person did not even introduce himself or ask any questions regarding my projects, CV or why I applied. Instead he asked me to grab a piece of paper and a pen and started to dictate math questions. The questions were what you would expect from a math exam in university and required you to have mathematical identities memorized. If you could not recall the required identity but found a way around it with a different solution, the guy seemed a bit confused and pushed back to "his" solution. No deep questions about statistics, machine learning, deep learning, data science, programming, etc.; just this 1 hour math exam where you are not allowed to have a peek into your linear algebra book or propose alternative solutions. It was a bizarre experience for a position that required a master's degree or PhD and a great waste of my time.