Chapter 2. A Pragmatic Approach

There are certain tips and tricks that apply at all levels of software development, ideas that are almost axiomatic, and processes that are virtually universal. However, these approaches are rarely documented as such; you'll mostly find them written down as odd sentences in discussions of design, project management, or coding.

In this chapter we'll bring these ideas and processes together. The first two sections, The Evils of Duplication and Orthogonality, are closely related . The first warns you not to duplicate knowledge throughout your systems, the second not to split any one piece of knowledge across multiple system components .

As the pace of change increases , it becomes harder and harder to keep our applications relevant. In Reversibility, we'll look at some techniques that help insulate your projects from their changing environment.

The next two sections are also related. In Tracer Bullets, we talk about a style of development that allows you to gather requirements, test designs, and implement code at the same time. If this sounds too good to be true, it is: tracer bullet developments are not always applicable . When they're not, Prototypes and Post-it Notes shows you how to use prototyping to test architectures, algorithms, interfaces, and ideas.

As computer science slowly matures, designers are producing increasingly higher-level languages. While the compiler that accepts "make it so" hasn't yet been invented, in Domain Languages we present some more modest suggestions that you can implement for yourself.

Finally, we all work in a world of limited time and resources. You can survive both of these scarcities better (and keep your bosses happier ) if you get good at working out how long things will take, which we cover in Estimating.

By keeping these fundamental principles in mind during development, you can write code that's better, faster, and stronger. You can even make it look easy.