Best to play it safe
The practice of Test-Driven Development is the most vital of the Extreme Programming disciplines. Its correct application offers the insurance to guarantee that one is not building a house of cards where the foundation will eventually fail to support a new addition. The fear of writing logic which conflicts with existing logic is alleviated by running unit tests before committing code to one's repository and having production and staging builds complied from automated processes which only build successfully if they are able to successfully run all unit tests.
Of all of the software consulting firms in Austin, Headspring Systems holds the most expertise in Extreme Programming and thus TDD. Our Agile Boot Camp™ trainings introduce XP virgins to the concept and underscore why the practice is critical to success. We also dive into mocking objects in tests with Rhino Mocks.