When our tests fail all we get is output in a terminal. Testing is core to the culture of Ruby, and the tools are sophisticated, but something big is missing from the workflow. Namely, a powerful debugger. Integrating Pry creates an interactive, enjoyable TDD workflow. In this talk, I'll recount the somewhat unique development experience that made me a believer. I'll demonstrate with Pry a responsive and immersive TDD cycle, taking a test to green before it exits its first run. Joel Turnbull is a Code Designer at Gaslight. He's been a staple in the Cincinnati development community for over 10 years. This is his first presentation at a Rails Conf.