As a ruby on rails developer, I’d like to promote the need for testing your applications. No matter how small or large your project, tests will be an invaluable tool to ensure working functionality as you add, delete and refactor code. And I can promise you, during the lifespan of your web app, your code will remain far from static. This is very obvious when you are working for a client. They change their minds constantly. But even if YOU are the client, as I have found myself to be as I work on my own, hobby rails sites, I’ve discovered that even I cannot resist the urge to make changes to my site, some that often break past functionality.