You built an API in .NET, put it in production, customers are using it, and now you have promises to keep. Promises related to the API contract and behavior. A good test suite will help you keep those promises by protecting against regressions. It will allow you to quickly iterate, add new features and expand

Software Testing Magazine

A good test suite helps maintain the promises of API contracts and behavior by protecting against regressions. It enables quick iteration, feature addition, and API expansion while being resistant to refactoring and providing fast feedback. This presentation discusses how to build such a test suite, including verifying API contract, API behavior, and addressing cross-cutting concerns like authentication and authorization. It covers pros and cons of various testing approaches, including test runtime, coverage, and the use of test doubles versus end-to-end testing with real data stores.

Building Test Suites for .NET Web APIs