It depends on what you want to debug. If you want to debug the creation of the package, I honestly don’t know. If you want to debug the application you are packaging, you don’t actually need to package it. You just need to have the correct structure for an Umbraco plugin in a local Umbraco installation. You can see a tutorial on how to build an Umbraco plugin here: https://blogit.create.pt////andresantos/2015/11/16/building-an-umbraco-7-backoffice-extension-part-i/. It’s a 3 part post.

If you have the code for your umbraco plugin running in a local installation of Umbraco you can debug the javascript in your browser developer tools and the server side code (dlls) if you attach the IIS express process to your project in Visual Studio.

Thanks!