Yes, that is the book. I was so excited when I was writing that book, but I received very little feedback from readers (a metric for evaluating my writing) comp

Yes, that is the book. I was so excited when I was writing that book, but I received very little feedback from readers (a metric for evaluating my writing) compared to other books I wrote. After writing that book for Apress (a wonderful publisher to work with, BTW), my 10th book with traditional publishers, I switched to writing eBooks on leanpub. This is more fun, since I can write about very niche topics and I can instantly update books with bug fixes and new material. Off topic, but writing is a lot of fun, and I never work with people who I don’t try to talk into writing at least one book.