DoorDash is doubling down on its efforts to embrace robots and enhance its on-demand food delivery service.

The San Francisco-based company is partnering with robotics startup Marble for a pilot program that will kick off initially in the San Francisco Bay Area.

Marble began life in San Francisco in 2015, but only emerged out of stealth back in April this year when it announced a tie-up with Yelp’s Eat24 food delivery service, with a handful of local restaurants opting into the pilot.

The eateries place their meals inside the bot’s cargo bays, and customers are texted an access code to unlock the door and take receipt of their food.

Above: Marble robots are wandering around San Francisco today.

Image Credit: Marble

Alongside other startups in the food delivery and logistics realm, such as Postmates, DoorDash has carved out a sizable niche for itself in terms of connecting the dots between restaurants, transport infrastructure, and hungry consumers. The company has raised nearly $190 million in funding since its inception back in 2013, and now operates in more than 500 cities across the U.S.

Marble isn’t the only such startup operating in the robotics food delivery space. An Estonia-based startup called Starship Technologies, created by Skype’s founders, has been testing its robots across U.S. and European cities since late 2015. Last year, European food delivery giant Just Eat claimed a “world’s first” ground-drone delivered meal using Starship Technologies’ robots in London, which was followed shortly after by Domino’s announcing a similar trial for pizza deliveries in a handful of European cities.

As it happens, DoorDash and Postmates have both previously tested out Startship Technologies’ robots for deliveries in the U.S. too. So it seems this latest exercise with Marble is all about continuing to test different setups and systems to see what works and what doesn’t. It’s still very much dipping its toe in the water.

“Marble has quickly established itself as an innovative thinker in the autonomous delivery space,” said Stanley Tang, cofounder and chief product officer at DoorDash. “This partnership expands upon our existing tests of new types of delivery technology, including robots, drones and electric bikes.”

Above: DoorDash & Marble

Image Credit: Marble

Starting from today in “a variety of Bay Area neighborhoods,” some customers may begin receiving their orders by a little four-wheeled unmanned machine. But it is worth noting here that Marble’s robots will initially be monitored by a person located nearby — it is still early days and it’s difficult to envisage a time in the immediate future when these machines will be left to operate entirely off their own volition.

“We’re excited to have our robots work with them to expand options for delivery and reduce urban congestion across communities to create a more enjoyable neighborhood experience,” added Marble CEO Matt Delaney.