Duncan McGregor published “Writing Software to Write About Writing Software - Part 1,” describing how he and his co-author (Nat Pryce) built software to help them write “Java to Kotlin: A Refactoring Guidebook” for O’Reilly’s publishing system, Atlas.

It’s a fascinating mechanism. Having written a book with similiar mechanisms - although nowhere near as completely as was done here, because this addresses a lot of the things I ran into while doing my own - this is fascinating stuff. The code is even online: https://github.com/java-to-kotlin/book !