Tests can form a normal part of the development process in some languages. You don’t need to go full TDD, but when you language’s tooling and IDE are designed f

Tests can form a normal part of the development process in some languages. You don’t need to go full TDD, but when you language’s tooling and IDE are designed for testing it can speed up your feedback loop. For example when writing in go in vscode, tests often sit in the same category of tooling as storybook and js hot reloadeder do. Being able to update a function and then run it with a set of inputs already defined automatically is really great. It also lets you workshop the API design (of a library) while your developing it. In some other languages I’ve found the tooling so painful to setup, that it’s rarely worth the effort.