You can push sales data from Shopify to Tend through Zapier. You do this by setting up a Zap that creates an "event" in Tend. Then, every time a sale occurs Shopify will push that data to Tend and assign that event to a contact with a matching email address.
For example, an event might be called "Sale - $100". When events are created, you'll be able to create segments based on them, search for them in the dashboard and see them on a contact's profile page.