The technical round was divided in three phases - phase -1 : intro and professional projects They asked about the projects I have contributed in my full-time tenure. Then, asked me to pick any one of them and explain every single detail about that project. As I have started with the data cleaning part, preprocessing and so on, they asked about the mathematical explanations and numbers, eg. how many columns were there in the raw data and then what are the final number of columns after feature engineering etc. Along with the maths, they were always asking to explain the small conecpts behind. After I complete explaining the whole project part, there were few follow-up questions asked -- 1. what changes would you have done, if you would be given this project today? 2. what are the reasons you chose the model, what you chose for this project? 3. Is there any other way you think, you could have solved the problem? Phase-2 : A test case and a problem statement They asked me about churn prediction and following some questions on the same- 1. what are the datapoints I would want to collect for the set of users who are wanting to end their subscription, and why? 2. How those datapoints are going to help you retain those customers? 3. what kind of a model you think would be fit for this problem? Phase-3: Python programming As the interview was occuring at hackerEarth, a real code editor is there on the screen. They gave me a problem which was a string problem, to store the unique characters and their count in a dictionary. Didn't ask any question on the solution I wrote. It was overall a very smooth interview and the interviewer was also very kind and helping to get the point.