Universal Principles of Design, Updated and Expanded Third Edition

184 Testing Pyramid

A multilayered framework to systematize testing and reduce defects.

The testing pyramid is a framework used to efficiently identify bugs and defects. The notion is that testing strategies vary in time, cost, and effectiveness and, therefore, an intentional mix of testing strategies should be used to balance cost with benefit.1

While there are many variations of the testing pyramid, all good variations include these three testing strategies:

1. Unit testing — Focuses on testing individual components or functionalities in isolation, independent of the greater system or context. Unit tests form the base of the pyramid because they comprise the bulk of testing efforts, estimated to be about 70% of the quality-assurance process. ...