There clearly are problems that are suited very well for TDD and others that aren't. I guess the suitability of TDD depends on how much a feature involves "how

There clearly are problems that are suited very well for TDD and others that aren't. I guess the suitability of TDD depends on how much a feature involves "how" rather than "what": Whenever it is clear what the feature should do (and what the feature's interface looks like) and the implementation is only about the "how", TDD seems to a very good idea. Almost every compiler-related task falls into this category. I just wrote a blog article on how to implement Typescript refactorings using TDD ([1]) and I don't think anyone could argue against using TDD there. If the feature is more about "what" (like UI/UX), TDD seems to be more of a burden than an useful asset. [1] https://blog.hediet.de/post/implementing_typescript_refactorings_with_hot_reloading https://blog.hediet.de/post/implementing_typescript_refactor...