There are probably dozen of possible books, but I think this one matches your description perfectly: https://www.goodreads.com/book/show/34927405-living-document... (https://www.goodreads.com/book/show/34927405-living-documentation) Just for reference, here is a classic about writing in general: https://www.goodreads.com/book/show/53343.On_Writing_Well
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