Fundamentals of Software Engineering

Chapter 3. Writing Code

Any fool can write code that a computer can understand. Good programmers write code that humans can understand.

Martin Fowler, British software developer, author, and international public speaker on software development

Writing code is, without a doubt, a very important part of software engineering. And while the act of coding is widely taught, the nuances of writing good code aren’t as evenly distributed. Just because you can write code to solve a problem doesn’t mean you should write code to solve a problem!¹ With the advent of artificial intelligence and agentic coding tools, the job of a software engineer is evolving to one with less hands-on development work and more bug fixing, correcting, and reviewing code generated by an eager AI tool. However, to be good at reviewing code, you must be good at writing code. It may seem counterintuitive, but writing good, clean code is an invaluable skill in the world of AI.

For better or worse, developers often have strong opinions on what constitutes good code or bad code, but metrics and tooling can give you insights and guidance. Tests are some of the best documentation money can buy. Code reviews, done well, can ensure that your team doesn’t rely on error-prone forms or overly clever code. Ultimately, code should be written to be read by humans.

Despite how it is often taught, programming is first and foremost a communication activity—and not just between the coder and the compiler. Don’t forget, the computer ...