When Serve shows up at your front door or office, you'll use your phone or a code to unlock the compartment and retrieve your items. The robot can carry up to 50 pounds of goods and can travel up to 30 miles on a single charge. Postmates also plans to collect items with Serve (especially in busy areas) and return them to its delivery hubs so delivery drivers can bring them to you.

Serve uses Velodyne Lidar and cameras to help it navigate, and Postmates claims it safely moves alongside pedestrians at walking speed and navigates obstacles such as fire hydrants. However, a human operator is always on standby to take over if needed. The robot also has a help button, along with a touchscreen for video chat. Serve can make its intentions clear using a light ring on top to provide turn signals.

Postmates expects to bring Serve to several cities next year and it's applied for a permit in San Francisco. It and several other logistics companies are working with the city's board of supervisors to develop a regulatory framework for autonomous deliveries.