I've been contacted by HR through LinkedIn, we arrange an initial call for the coming week. First call very straight forward , some questions about my experience and a brief overview about the company. Then I've been sent a coding challenge which consisted in implementing a San Francisco vehicles map with some real-time updates, with d3js and some frontend library (I choosed react) Sent the code and after a few days the recruiter got back to me saying they liked my code and wanted to get forward with the last step. Last step has been a 3h face to face interview on Skype , with 3 different engineers , only coding , nothing related to my previous challenge. They asked me to implement an algorithm to calculate the combinations of an array of array Then to implement a simple LRU cache with some specific requirements together with the unit tests. Then the last guy asked me to implement a function to reduce a tree (essentially an object with children) recursively. The process has been quite long, the coding test was not too difficult but the last stage was too long and one of the guy was quite arrogant.