Refactoring at Scale

Chapter 2. How Code Degrades

Successfully running a marathon is an impressive feat. While I’ve personally never taken on the challenge, quite a few of my friends have. What may surprise you, however, is that the large majority of these friends were not avid runners before deciding to sign up for their first half or full marathon. By sticking to a regular, sustainable training schedule, they were able to build up the necessary endurance in just a few months.

Most of my friends were already in good physical shape, but if your goal is to run a marathon and most of your current physical activity involves getting up from the couch to grab a bag of chips from your pantry, you will have a much more difficult time. Not only will you first have to build up the cardiovascular and physical endurance of a regularly active person, you’ll have to adopt new habits around habitual exercise and eating healthy food (even when all you want to do is settle into a comfy chair with a big, cheesy slice of pizza).

Small fluctuations in training can lead to serious setbacks. If you haven’t gotten enough sleep or get caught off-guard by a scorching-hot day, you will tire more quickly, compromising your ability to run your target distance. Even in peak marathon form, you have to be prepared for the unknowns on the day of the race. It might rain; your laces might break; you might be stuck in a tight crowd of runners. You learn to master the variables you can control but must be willing and ready to think ...