Added Store › Customers. Each buyer email has one customer, with their orders, what they spent after refunds, and their first and last order. Name, phone, tags and notes are edited on the customer's page, and Add to Contacts links the customer to a contact.
Save filters (spent over an amount, bought a product, no order in a number of days, number of orders, tag) as a segment, export customers as CSV, and limit a discount to a segment.
A buyer signed in to Magpie can choose an address saved from an earlier order at checkout. Export personal data and Erase personal data answer a customer's data request; erasing keeps order amounts.