In this episode, embedded systems expert Jacob Beningo explores test-driven development (TDD) as the fourth step to modernize embedded software development. He addresses common misconceptions that TDD doesn't work for embedded developers, demonstrates how proper software architecture enables effective testing, and explains the mental shift required to write tests before production code for higher quality, more reliable embedded systems.

Key Takeaways:

• Test-driven development requires writing tests first, then production code to make tests pass, which feels counterintuitive initially but improves over time
• Properly architected embedded software with decoupled hardware layers makes TDD highly effective for application code
• The mental adjustment to TDD takes several weeks but results in faster overall development and higher code quality
• TDD provides immediate feedback when changes break existing functionality through regression testing
• Multiple testing types are available: unit, integration, system, regression, performance, and user acceptance testing
• System-level TDD can drive development from user requirements down to individual components
• AI tools can accelerate TDD processes while maintaining rigorous testing standards
• A simple push button module can require 98 tests and 4,000 checks for complete validation
• 100% test coverage is a worthy goal but doesn't guarantee bug-free code
• TDD initially feels slower but dramatically reduces debugging time and improves long-term development velocity