TDD: The Hard Parts - Getting Started with Test-Driven Development

The Pragmatic Embedded Podcast · 30 Sept 2026 · 45m

What this episode covers

Jeff Gable and Luca Ingianni discuss the practical challenges of adopting Test-Driven Development (TDD) in embedded software, specifically addressing the difficulty of starting with a blank screen. They outline a process that begins with decomposing systems into modules, sketching test ideas as bullet points, and writing test outlines in plain English before implementing code. The hosts highlight how LLMs can help overcome the fear of the empty screen but create new traps by generating overwhelming or nonsensical test suites, requiring developers to review test code more thoroughly than production code to ensure it accurately reflects the desired module interface and behavior.

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  • Embedded.fm · 57m

    109: Resurrection of Extreme Programming

    James Grenning, founder of Wingman Software and author of 'TDD for Embedded C', discusses the resurgence of Extreme Programming and Test-Driven Development (TDD) for embedded engineers. He explains how TDD prevents bugs and improves predictability, contrasting it with 'debug later' practices, and details his use of CyberDojo and WebEx to deliver remote training. Grenning also critiques modern Scrum for focusing on management cycles while neglecting technical excellence, advocating for the original engineering-focused practices of Extreme Programming.

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