The App Engine Node.js runtime has no language or API restrictions. Developers can use their favorite Node.js modules by declaring them in a package.json file. App Engine will automatically install them after deployment. Thanks to Google’s close relationship with Node.js — it is a sponsor of the Node.js foundation — Google offers a number of Node.js client libraries that make it easy for developers to also use other Google Cloud Platform products, such as Cloud Datastore.
Developers can try Node.js on App Engine using App Engine’s free usage tier and Google has published a quickstart guide to help developers get started.