Green CI doesn't guarantee good tests. Mutation testing reveals whether your test suite actually catches bugs or just exercises code. Learn how mutation testing works, when it's worth the cost, and.
What is each test level responsible for? Learn the scope, objectives, test basis, and typical defects for component, integration, system, and acceptance testing.
Unit, integration, E2E, manual, exploratory — every type has its place. Learn the test pyramid vs testing trophy debate and how to make smart trade-offs.