Head First Software Architecture
by Raju Gandhi , Mark Richards , and Neal Ford
Copyright 2024 Defmacro Software L.L.C., Mark Richards and Neal Ford. All rights reserved.
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978-1-098-13429-7
Chapter 1. Software Architecture Demystified: Lets Get Started!
A Note for Early Release Readers
With Early Release ebooks, you get books in their earliest formthe authors raw and unedited content as they writeso you can take advantage of these technologies long before the official release of these titles.
This will be the 1st chapter of the final book. Please note that the GitHub repo will be made active later on.
If you have comments about how we might improve the content and/or examples in this book, or if you notice missing material within this chapter, please reach out to the authors: MarkRichards (mark@wmrichards.com), Neal Ford (neal.ford@gmail.com), and Raju Gandhi (raju.gandhi@gmail.com).
Software architecture is fundamental to the success of your system. This chapter demystifies software architecture. Youll gain an understanding of architectural dimensions and understand the differences between architecture and design. Why is this important? Because understanding and applying architectural practices helps you build more effective and correct software systemsthose that not only work better functionally, but also meet the needs and concerns of the business and continue to operate as your business and technical environments undergo constant change. So, without further delay, lets get started.
Building your understanding of software architecture
To better understand software architecture, think about a typical home in your neighborhood. The structure of the home is its architecturethings like its shape, how many rooms and floors it has, its dimensions, and so on. A house is usually represented through a building plan, which contains all the lines and boxes necessary to know how to build the house. Structural things like those shown below are hard to change later and are the important stuff about the house.
Note
The building metaphor is a very popular one for understanding software architecture.
Architecture is essential for building a house. Can you imagine building one without an architecture? It might turn out looking something like the house on the right.
Like physical structures, architecture is essential for building software systems as well. Have you ever come across a system that doesnt scale, is not relaible, or is too difficult to maintain? Its likely not enough emphasis was placed on its architecture.
Exercise
Gardening is often used as a metaphor for describing software architecture. Using the space below, can you describe how planning a garden might relate to software architecture? You can see what we came up with at the end of this chapter.
Building plans and software architecture
You might be wondering how the building plans of your home relate to software architecture. Each is a representation of the thing youre building. So what does a building plan of a software system look like? Lines and boxes of course.
A building plan specifies the structure of your homethe rooms, walls, stairs, and so onin the same way a software architecture diagram specifies its structureuser interfaces, services, databases, and communication protocols. Both artifacts provide guidelines and constraints, as well as a vision of the final result.
Sharpen your pencil
What features of your home can you list that are structural and related to its architecture? You can find our thoughts at the end of this chapter.
Note
Use this space to write down your ideas.
Did you notice that the floor plan for the house above doesnt specify the details of the roomsthings like the type of flooring (carpet or hardwood), the color of the walls, and where a bed might go in a bedroom? Thats because those things arent structural. In other words, they dont specify something about the architecture of the house, but rather its design.
Note
Dont worryyoull learn a lot more about this distinction later in this chapter. Right now, just focus on the structure of somethingin other words, its architecture .
The dimensions of software architecture