Nosto for Shopify supports ratings and reviews powered by Stamped.IO. In order to begin leveraging Stamped.IO's ratings and reviews in Nosto, you'll need to install Stamped.IO's app for Shopify.
Once you have installed and configured Stamped.IO on your Shopify store, you'll need to contact our support personnel who can enable the integration for you. This is a one-time operation after which Nosto begins collecting the rating and review metadata automatically. There is no additional configuration required on Nosto's end.