Test Framework
Under Code, Test Framework covers libraries and tools whose primary job is to author, organize, and run automated tests—runners, assertion libraries, mocks, and chart/template testers. This is not Unit Testing or Integration Testing themselves (those are Technique notes); it is the concrete software you pick to implement them.
Sibling subcategories: Language, Library, and Framework (application stacks). Tag an item here when the product exists mainly to support test execution—e.g. Helm Unittest for Helm Chart templates, TestContainer for integration dependencies—not when testing is a side feature of a larger platform.