30: Eventually Lightning Strikes
James Grenning, author of 'Test Driven Development for Embedded C' and founder of Renaissance Software, explains how TDD reduces bugs and improves design in embedded systems. He argues that manual testing is unsustainable because the cost of retesting grows exponentially, leading to hidden defects that cause late-stage failures. Grenning advocates for getting code off the target hardware to run on PCs using mocks and fakes, which forces modularity and allows engineers to build confidence before hardware is available. He emphasizes that TDD is not just about testing but about driving SOLID design principles, such as single responsibility, by making complex code difficult to test.