Ford has begun various trial delivery services with its self-driving car prototypes across the United States, but now it has announced its most ambitious program yet. The automaker said on Wednesday it has partnered with Walmart and Postmates for a self-driving delivery service.

The program will see all sorts of goods from Walmart delivered to customers, including groceries, toiletries, and other goods. Postmates is already a Walmart and Ford partner, which lets the automaker get the latest self-driving pilot program off of the ground rather quickly.

And the service will complement Walmart's growing delivery option. The discount retailer uses personal shoppers to gather a customer's order and Postmates delivers the goods. Ford will use research vehicles to better understand what works, and what doesn't, for customers that opt to use the delivery service.

The program will also reveal what kinds of goods Ford can deliver without issue, and where it will need to improve to ensure a self-driving car can transport an item feasibly. This is especially true if a self-driving car is scheduled for multiple deliveries with perishable items onboard.

It isn't Walmart's first rodeo when it comes to self-driving cars, though. The retailer previously partnered with Waymo to offer store discounts for those involved in the self-driving car company's "Early Riders" trial. But, the riders had to be onboard the self-driving car. Ford wants to pick up a customer's goods and deliver them.

Ford has also run delivery operations across Miami-Dade county in Florida for tacos and pizzas, which both began this year. Last month, the automaker announced it will be the first to bring self-driving cars to Washington, D.C. as it expands its operations from Detroit, Pittsburgh and Miami.