Software-intensive systems are like that. They grow, they evolve, sometimes they wither away, and sometimes they flourish. The concept of technical debt is central to understanding the forces that weigh upon systems, for it often explains where, how, and why a system is stressed. In cities, repairs on infrastructure are often delayed and incremental changes are made rather than bold ones. So it is again in software-intensive systems. Users suffer the consequences of capricious complexity, delayed improvements, and insufficient incremental change; the developers who evolve such systems suffer the slings and arrows of never being able to write quality code because they are always trying to catch up.

What delights me about this present book is its focus on technical debt and refactoring as the actionable means to attend to it.

When you have got a nagging tiny gas leak on a city block, a literal smell will lead you to the underlying cause. Software-intensive systems are like that as well, although the smells one may observe therein are far more subtle and invisible to all the senses save to the clever cognitive ones. As you read on in this book, I think you will find one of the more interesting and complex expositions of software smells you will ever find. Indeed, you have in your hand a veritable field guide of smells, sort of like the very real Birds of the West Indies, except about software, not sparrows.

Abstraction, encapsulation, modularization, and hierarchy: these are all elements fundamental to software engineering best practices, and you will see these highlights explained as well. In all, I think you will find this a delightful, engaging, actionable read.