Clean architecture characteristics

Here’s a summary of the ideas behind the clean architecture by Uncle Bob:

You should be able to test your business logic without any server or UI running.
Inner circles are policies, outer circles are mechanisms. In other words, inner circles say WHAT, and outer circles say HOW.
It’s independent of the UI, the database, the framework.
The UI is a detail. The database is a detail. Business rules should not know what specific database you are using.
Dependencies point innwards.
The UI and framework are plugins of the business rules.
A good architecture allows you to defer decisions. Later is always better, because you have more information later.

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