Shift-Left Testing

A Shift-Left Testing is a proactive approach to software quality that moves the testing process to an earlier stage in the development lifecycle. Instead of waiting for the software to be fully developed, this practice encourages developers and testers to start testing during the requirements, design, and coding phases. The goal is to find and fix defects sooner, which is more efficient and less costly.

Example: In a traditional model, a login feature might be tested only after it's fully built and passed to the QA team. With Shift-Left Testing, the developer writes unit tests for the login code as they're building it, and the QA team reviews the requirements for potential ambiguities before a single line of code is written. This early, collaborative effort helps catch bugs and design flaws long before the feature is even ready for full-scale functional testing.