GammaRay is a high-level introspection tool for Qt programs that enables you to visualize and manipulate application behavior at runtime. In this talk we will look at new capabilities and features GammaRay has gained since last year, and how those assist you in solving real-world debugging and profiling problems. When creating applications we strive to use higher-level frameworks in order to obtain results quickly and reduce development effort as well as long-term maintenance cost. This however provides a few challenges during debugging and profiling. With conventional instruction-level tools we need to have a reasonably deep understanding of the implementation of the frameworks, libraries and components we use, to interpret the results correctly. Tools with an understanding of the building blocks we use mitigate this problem. GammaRay is such a tool for Qt. Following last year’s talk on the same subject, we’ll look at the most important changes in GammaRay in its recent releases, ranging from improvements in object tracking to new visual aids for layouting and debugging Qt Quick UIs. We will then see how to apply those to a number of debugging and profiling examples. All examples are based on real-world problems KDAB engineers encountered in their daily work, and aim at giving you an idea on how GammaRay can help with problems you might encounter in your own Qt application.