I will agree that these tests can be overly domain specific, but I also think that the desire to have engineers with great breadth of knowledge is a good one.
I'm with you, breadth of knowledge is important. That is certainly what my role demands of me and I like it, but in being broad I think we sacrifice depth in some of these categories. I think this particular test is incredibly general and is well suited to many full stack developers, I agree with the author that extending it to a sockets implementation would make it even more fun.
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