This sample Dropwizard application runs on Google Cloud Platform's App Engine Flexible Environment.
Download all the bits from Google (you'll want the gcloud command line utility). Once you have that, go to the developer console and create a new project. After that, run the following:
gcloud config set project <project id>
mvn gcloud:deploy
If all succeeds, you should be able to browse to http://<project-id>.appspot.com/ and receive a lovely greeting.