Requirements: * Java 6 * Vaadin 6.8 * Trunk build of GWT, e.g. http://artur.virtuallypreinstalled.com/gwt-trunk-20120607.zip How to use: * Add this add-on jar to your build path * Download the GWT trunk build and add to your build path. Remove any old GWT jar references (the Vaadin plug-in for Eclipse automatically adds these) * Recompile the widget set as always. This will fail if you use an old version of GWT. * Start the code server (Run com.google.gwt.dev.codeserver.CodeServer ) * Add ?superdevmode to your application URL To do remote debugging, for instance from a phone or tablet, add ?superdevmode= to the url, e.g. ?superdevmode=myothermachine:9876 Note that Tomcat seems to conflict with the CodeServer so if you have Tomcat on your code server classpath, be sure that the GWT trunk jars are before the Tomcat jars on the classpath. Note also that there is no need to run CodeServer in debug mode. It will recompile the widgetset when you refresh the browser, not when you modify your Java code. For more info on SuperDevMode, see http://vaadin.com/blog/-/blogs/vaadin-and-superdevmode Note that Vaadin 7.0.0.alpha3 contains this add-on built-in.