Hi, The latest Moose image comes with GTInspector and GTDebugger installed as default tools. GTDebugger is the result of the excellent work of Andrei. At the moment, the GTDebugger only replicates the behavior of the default debugger. The custom debuggers will follow soon. Both of these are part of the GToolkit. Just for reference: - GT-Debugger has 499 lines of code. - GT-Inspector has 484 lines of code. In other words, you could read the full code in the lunch break :). Here is a screenshot showing them: https://www.dropbox.com/s/hzxg82nzz163gb1/2013-11-15%2019.20.42%20-%20gtdebu... If you see issues, please report them. Cheers, Doru p.s. Unfortunately, we could not install the GTInspector alone in the Pharo image because the SpecDebugger still depends on the inspector being implemented in Spec. -- www.tudorgirba.com "Every thing has its own flow"