Microsoft is reportedly working on technology that would eliminate cashiers and checkout lines from stores, in a challenge to Amazon.com's automated grocery shop.

According to Reuters, Microsoft is developing systems that track what shoppers add to their carts. Microsoft has shown sample technology to retailers from around the world and is said to have already talked with Walmart about a potential collaboration.

It is not clear how soon Microsoft would bring an automated checkout service to market, if at all, or whether its technology would be the answer retailers are looking for.

Microsoft declined to comment.

Amazon Go, a highly automated store, opened to the public in Seattle in January. Amazon customers scan their smartphones at a turnstile to enter. Cameras and sensors identify what they remove from the shelves. When customers are finished shopping, they simply leave the store and Amazon bills their credit cards on file.

Microsoft ranks No. 2 behind Amazon in selling cloud services that are key to running e-commerce sites.