The Crux by Richard Rumelt. The sequel to his previous book Good Strategy, Bad Strategy. I think you need to read that first to best appreciate the Crux but it’s a good addition and emphasizes finding out where to focus, aka “the crux”. I wrote this Collect, Cluster, Filter (x2), Alternatives — Jason Yip — Medium based on this book.
A Spy’s Guide to Strategy by John Braddock. This is the 2nd book in his spy series. I read a Spy’s Guide to Thinking last year. Like the first book, this is short and entertaining. Looking forward and reasoning backward, zero-sum and positive-sum games.
Uncommon Sense Teaching by Barbara Oakley, Beth Rogowsky, and Terrence J. Sejnowski. I read this after taking the Uncommon Sense Teaching specialization on Coursera. The best reference I know of about effective teaching.
Software Estimation without Guessing by George Dinwiddie. The best book currently on software estimation.
Designing Data-Intensive Applications by Martin Kleppman. This one is extensive. The go to reference to learn how to reason about and design data-intensive applications.