There was a great discussion here on HN a few months ago about DRY [0] and how developers generally get the concept wrong. Specifically, it’s not about removing

There was a great discussion here on HN a few months ago about DRY [0] and how developers generally get the concept wrong. Specifically, it’s not about removing duplicated code. It’s about ensuring there’s a single source of truth for a given piece of knowledge in your application. For example, if you’re calculating interest on purchases all over the place and hard coding the rate everywhere, it should be unified into a single function or method, so that there’s one source of truth for calculating interest. If you just have some code that looks similar but doesn’t represent “knowledge” that is being duplicated, DRY does not apply. Some folks in the comments mentioned they liked to use SPoT as an acronym that’s a bit clearer, and I’ve been using that since then in code reviews. [0]: https://news.ycombinator.com/item?id=22329787 https://news.ycombinator.com/item?id=22329787