Understanding the Four Rules of Simple Design

From 2009 to 2014, I traveled the world working with software developers, both individually and in teams, to improve their craft. I did this primarily through a training workshop format called coderetreatі. During these day-long events, we worked on improving our ability to make good choices around the minute-by-minute decisions we make while writing. Over those years, I watched thousands of pairs of programmers work on exactly the same system, Conway’s Game of Life⁴. As a facilitator of these coderetreat workshops, I had the unique opportunity to provide feedback, both direct and through questions, on improving the act of writing adaptable, simple code. As time progressed, I began to see patterns arise, common techniques and designs that spanned languages, stayed the same between companies, and crossed national borders. My job as a facilitator was to ask the questions that would push people past these common ideas, gently (and sometimes not so gently) prodding the participants into opening their minds to alternate ways to approach their design. This book contains some of those patterns, designs and my responses to them.