Thanks to @lateinteraction for creating @DSPyOSS and encouraging me out of my imposter syndrome, and @dbreunig for convincing @OReillyMedia this topic was a good bet. Thanks @LakshyAAAgrawal for making GEPA the optimizer that has been dominating every prompt I try. Also @isaacbmiller1 the lead maintainer of DSPy, @jamesaphoenix12 coauthor of my last book, @Shashikant86 and Sriharsha Annamaneni for technical review. Thanks to my colleagues @danshipper and @kieranklaassen for reading and endorsing the book before it was published. Thanks also to the team at O'Reilly, Jeff, Nicole, Beth for making my writing fit to print. The wider DSPy community @MaximeRivest, @getpy, and @_rchaves_ and everyone who was patient enough to explain to a naive prompt engineer why we didn't need prompts anymore. Finally thanks to my wife and kids (who thankfully aren't on X), for giving me 9 months of evenings and weekends to get this done.