Testify is a .NET unit test assertions, test data creation and contract verification framework. It's not dependent on any specific unit testing framework, and can be used with the unit test framework of your choice.
Testify Assertions use a fluent syntax that makes it easy to discover what assertions are valid for the actual value being tested through strong IntelliSense support. In addition, because of the fluent syntax, it is easy to add your own custom assertions.
Testify's @Testify.AnonymousData allows you to create test data and objects that are necessary for the test to run but that aren't otherwise of interest. This helps to decouple the test from non-relevant production code (making the tests less "brittle"), as well as helps to clarify what's actually being tested. For more information see Using AnonymousData.
Testify Contract Verifiers make it easy to test that a type adheres to a contract by running a suite of tests against the type.