Sébastien Deleuze, a Spring guru and Kotlin expert, shares invaluable insights on optimizing runtime efficiency. He dives into the evolution of the Spring Framework and discusses innovative features like Spring Native and the interplay between Java and Kotlin. The conversation also covers advancements in Java, including null safety and smart switch expressions. Sébastien highlights the significance of application startup speed in cloud environments and explores the competitive dynamic between Java and Kotlin, forecasting a bright future for both in enterprise solutions.