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# YAGNI

**You aren't gonna need it**

This is a mantra from Extreme Programming usually tied with agile software teams. It essentially means implementing features that you anticipate needing in the future. Martin Fowler discusses this concept in detail in the blog post [YAGNI](https://martinfowler.com/bliki/Yagni.html)

YAGNI argues that you should not implement features that you anticipate needing.

Building Features today for the future can be costly: 1. You devoted dev time for something that is not feasible and developer time is money. 2. You have to maintain this new feature in tandem with other features. 3. You falsely assume requirements that are wrong and you need to rewrite. 4. You are adding complexity to a code base for a perceived requirement. 5. You should wait until the feature is truly needed implementing it prematurely.


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