If any title in the Cambridge Elements series was especially designed to catch my interest, it would be Theoretical Computer Science for the Working Category Theorist. Not, of course, that I am in any sense a ‘working category theorist’, but I’m certainly interested, and know just a bit. And I know a smidgin too about computability theory. So I, for one, should be an ideal reader for an accessible short book which sets out to give more insights as to how the two are related. The introduction notes that there are a number of texts aimed at the computer scientist learning category theory (like the excellent Barr and Wells, Category Theory for Computing Science); but Noson Yanofsky promises something quite different, aimed at someone who already knows the basics of category theory and who wants to learn theoretical computer science.
It most certainly didn’t work for me. The author has a line about the central relevance of the notion of a monoidal category here, but makes it quite unnecessarily hard going to extract the key ideas. Indeed, overall, this just strikes me as very badly written. Careless too. What, for example, are we to make of slapdash remarks like “the German mathematician Georg Cantor showed that sets can be self-referential” or “Kurt Gödel showed that mathematical statements can refer to themselves”? (And on Gödel, I doubt that anyone who isn’t already familiar with the proof of Gödelian incompleteness theorems from the unsolvability of the Halting problem is going to get much real understanding from the discussion on pp. 71–72.)
I could go into a lot more detail, but to be honest I found the book far too disappointing to want to put in the effort required to disentangle things enough to make for useful comments. Sorry to be so negative. And your mileage, of course, might vary …
[Also see Peter F’s comment.]