App-enabled cab service Uber is announcing today that its UberRush application programming interface (API) is now available for any developer who wishes to bring an on-demand delivery component to their own applications. This follows a private beta that was first announced in January, shortly after the launch of the UberRush delivery service.

Companies like Google (with Google Express), Harris Teeter, Nordstrom, and Walmart have already integrated UberRush into their services, and now other companies will be able to do that in a self-service fashion. This means that drivers standing ready to make deliveries on your behalf are now just an API call away. Uber has already mastered the art of getting people from place to place, and that same expertise can be transferred to the delivery of goods.

The company is pointing to a few early implementations of the API: on-demand pizza delivery app Pythagoras, on-demand dry cleaning service Dryv, on-demand meal delivery services Ando and Mealmade, and on-demand drone rental business Up Sonder. These early adopters might not be the biggest names, but Uber is nevertheless optimistic.

“I think the aspirations are very, very big — it’s a very big bet for the company,” UberRush product manager Calvin Lee told reporters in a briefing at Uber headquarters in San Francisco earlier this week.

And Uber is committing staff resources to UberRush. Hundreds of people are currently working on the Uber Everything team (out of some 8,000 total Uber employees around the world), a spokesperson said.

It’s unclear if delivery could one day eclipse the core ride-sharing service in terms of revenue. But from the outside, UberRush does appear to have the potential to become a serious revenue source, one that could hold a prominent place in Uber’s quarterly financial statements for years to come.

But now that the API is out the door, Uber has another big assignment: expanding the geographical reach of the UberRush service itself. Currently it is only available in San Francisco, Chicago, and New York City. Uber drivers who are already carrying passengers can also sign up to do UberRush deliveries, and there are some drivers who are only delivering goods, Lee said. But at this moment, drivers aren’t transporting things like pizzas in the front seat while they’re also shuttling a couple in the back seat.

“We’re always looking for ways to be a lot more efficient in terms of how we spend drivers’ time,” Lee said. “We are interested in these big logistics problems that come from moving both people and things.”

San Francisco-based Uber started in 2009. Earlier this month, the company disclosed that Saudi Arabia’s Public Investment Fund had invested $3.5 billion.