How do NUnit test attributes differ from xUnit’s?

Short answer: NUnit uses [Test] for test methods, whereas xUnit uses [Fact]. NUnit uses [SetUp] and [TearDown] for setup and cleanup, while xUnit uses constructors and IDisposable. NUnit supports [TestCase] for parameterized tests, xUnit uses [Theory] with [InlineData]. NUnit has more built-in attributes like [Category] for grouping tests.

Real-world example (ShopNest)

ShopNest unit tests cover pricing and discount rules so a bad coupon change fails in CI before customers see it.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.