FedEx announced the fdx.com platform in January at the National Retail Federation’s Big Show and spent the next eight months in a quiet rollout.

It says brands of all sizes have bought in, including Z Supply, an apparel company with a presence with more than 3,000 retailers in the U.S. It, FedEx says, has already reported single-digit results in revenue and conversion rates.

Amazon has been providing these services for its sellers for years, says Santosh Kumar, the Lillian and Morrie Moss Chair of Excellence Professor in Computer Science at the University of Memphis.

“Amazon is the marketplace. It’s serving those who sell their products on Amazon, including handling their warehousing and returns.

“It leaves all of these brick-and-mortar retailers who are losing more and more business to Amazon, but they don’t want to move to Amazon because it charges hefty fees,” Kumar said.