Believe it or not, it's partly thanks to you, HN, that I wrote this book in 2014 in the first place [1]! It's humbling to see it listed here again now that the text has become available under a CC BY-ND license. Thank you for your help in spreading the word.
All this attention (read: likes, shares, and page views) is making me wonder whether it's worthwhile to write an update (or even a second edition). What do you think? What would you like to see changed or added?