Software Architecture Hardparts is a book I read.
The book discusses approaches to difficult problems in distributed systems.
It might be easier to read if you have already read Fundamentals of Software Architecture: A Comprehensive Approach and Building Evolutionary Architectures: Support Constant Change beforehand.
The book organizes thoughts and approaches on how to reconstruct architecture.
Personally, my favorite chapter is the last one, "Chapter 15: Building Your Own Trade-off Analysis." Although it slightly deviates from the main content of the book, it provides a way of thinking about architectural strategies.
As an aside, I participated in the translation review of this book, so I have a personal attachment to it.
