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Fundamentals of Software Architecture by Neal Ford, Mark Richards

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Preface: Invalidating Axioms


a statement or proposition which is regarded as being established, accepted, or self-evidently true.


Mathematicians create theories based on axioms, assumptions for things indisputably true. Software architects build axioms as well, but the software world is, well, softer than mathematics: fundamental things continue to change at a rapid pace in the software world.

The software development ecosystem exists in a constant state of dynamic equilibrium: while it exists in a balanced state at any given point in time, it exhibits dynamic behavior over the long term. A great modern example of the nature of this ecosystem follows the ascension of containerization and the attendant changes wrought: tools like Kubernetes didn’t exist a decade ago, yet now entire software conferences exist to service its users. The software ecosystem changes fractally: one small change causes another small change; when repeated hundreds of time, it generates a new ecosystem.

Architects have an important responsibility to continue to question assumptions and axioms left over from previous eras. Many of the books about software architecture were written in an era that only barely resembles the current world. In fact, the authors believe that we must question fundamental axioms on a regular basis, in light of improved engineering practices, operational ecosystems, software development processes—everything that makes up the messy, dynamic equilibrium where architects and developers work each day.

Careful observers of software architecture over time witnessed a slow evolution of capabilities. Starting with the engineer practices of eXtreme Programming, continuing with Continuous Delivery, the DevOps revolution, microservices, containerization, and now cloud-based resources, all of these innovations lead to new capabilities and tradeoffs. As a good illustration of this perspective shift, for many years, the tongue-in-cheek definition of software architecture was “the stuff that’s hard to change later”. Then, the microservices architecture style appeared, where change is a first-class design consideration.

Each new era requires new practices, tools, measurements, patterns, and a host of other changes. This book looks at software architecture in modern light, taking into account all the innovations from the last decade, along with some new metrics and measures suited to the new structures and perspectives now available.

One possible subtitle of our book was “An Engineering Approach”. Developers have long wished to change software development from a craft, which skilled artisans can create one-off works, to an engineering discipline, which implies repeatability, rigor, and effective analysis. While software engineering still lags behind others by many orders of magnitude (to be fair, software is a very young discipline compared to most other types of engineering), architects have made huge improvements, which we reflect. In particular, modern agile engineering practices have allowed great strides in the types of systems architects design and the attendant engineering practices that enable them.

We also address the critically important issue of tradeoff analysis. Architects often appear grumpy because the binary clarify of developers melts away. As a software developer, it’s easy to become enamored with, enthusiastic about, and even evangelical about a particular bit of technology or approach. However, architects must always soberly assess the good, bad, and ugly of every choice, and virtually nothing in the real world offers convenient binary choices—everything is a tradeoff. Given this pragmatic perspective, we strive eliminate value judgments about technology and focus on analyzing the real tradeoffs to equip our readers with an analytic eye towards technology choices.

This book won’t make someone a software architecture overnight—it’s a nuanced field with many facets. We want to provide existing and burgeoning architects a good modern overview of software architecture and its many aspects, from structure to soft skills. While this book covers well known patterns, we take a new approach, leaning on modern lessons learned, tools, engineering practices, and other input to build a modern book on software architecture.

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