Takes a platform, a JDK (containing a JRE), your JAR and a json file specifying the VM args and packages it for either Windows (folder), Linux (folder) or Mac OS X (App Bundle). The package will contain a native executable so your app kinda looks like a native app. It will invoke the bundled JRE using the arguments specified in the config.json file.
I'll add tree shaking and icon support when i have more time, PRs welcome. Feel free to laugh at my horrible C/C++.