The Core Idea
Software development is a craft, not just a science. The best programmers aren’t the ones who know the most algorithms — they’re the ones who make good decisions consistently, communicate well, and take ownership of their work.
What Stuck With Me
The “broken windows” metaphor: one piece of neglected code invites more neglect. Fix the window immediately or board it up with a comment explaining why it’s deferred. Don’t let entropy win by default.
DRY (Don’t Repeat Yourself) is presented more nuanced than most people apply it. It’s not about eliminating all duplication of code — it’s about eliminating duplication of knowledge. Two functions that look identical but represent different concepts shouldn’t be merged.
Who Should Read This
Early-to-mid career developers especially. The advice ages well because it’s about principles, not specific technologies. The 20th anniversary edition updates the examples without changing the philosophy.