Sure, it goes farther than, say, Pandoc, in giving you access to an underlying programming environment as a writer. But to double down on my quibble, when I go

Sure, it goes farther than, say, Pandoc, in giving you access to an underlying programming environment as a writer. But to double down on my quibble, when I go into a bookstore, or on O'Reilly (or now, Amazon, sniff), what's on offer are books. Even if on github and similar, what's on offer there is source of various languages and markup, which go to produce a book. I just can't see any final, static rendering of source as a "program." I would consider Stephenson's Young Lady's Illustrated Primer, or anything that aspires to that, as a program. https://en.wikipedia.org/wiki/The_Diamond_Age https://en.wikipedia.org/wiki/The_Diamond_Age