Building serverless architectures is hard. At least it was to me in my first attempt to design a loosely coupled system that should, in the long term, mean a good bye to my all-time aversion towards system maintenance.
Music information retrieval is also hard. It is when you attempt to start to grasp the underlying theoretical framework and submerge yourself into scientific papers which each yield a different approach for extracting some feature out of digital audio signals. It is a long way until MFCC starts to sound natural. I have been there.