Found in 2 comments on Hacker News
lapcat · 2023-11-20 · Original thread
I highly recommend "The Maker of Dune", if you can find a copy of the book somewhere. https://www.amazon.com/Maker-Dune-Insights-Science-Fiction/d...
lapcat · 2023-03-15 · Original thread
"The Maker of Dune" adds a lot of personal insight to his work. https://www.amazon.com/Maker-Dune-Insights-Science-Fiction/d...

I used to have a copy but sold it at some point. Apparently it's hard to find now, given the very high price.

Update: The entire book is in the Internet Archive! https://archive.org/details/the-maker-of-dune-insights-of-a-...

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