Explore the theoretical underpinnings of modern software engineering practices in this 41-minute conference talk from Devoxx Greece 2025, where James Lewis examines the concepts of Value and Flow. Discover why today's sensible defaults in software engineering—such as Accelerate metrics, Team Topologies structures, and Microservices—are effective through the lens of Information Theory and Complexity Science. Gain insights into the domain model of software development and understand the mathematical reasons behind reducing batch sizes to improve value delivery. This thought-provoking presentation delves into the mechanics of how work works, offering a scientific perspective on turning ideas into running software.