I wish they where less common, but it does seem like a good idea to do some challenges before interviewing especially for low to mid level jobs. There are a number of good sources. I like “Project Euler”. a lot of the popular options like hackerrank or codesignal are very gamified. Go for it if that is your thing, but i find scores and points feel very dehumanizing for me.

I absolutely detest leetcode style interview questions. I am good at solving problems and writing modular code. I am not good at writing search algorithms. Any guesses which one of those is more relevant to my job? 99% of development does not involve writing low level algorithms, because guess what someone else already did that for you, it’s called a library!

Had to do one during a recent interview. Had no issues and took 10 minutes during the call. They then requested I do an at home code test that they said took most people 8 hours. I had another offer already so I told them to pound sand.