The fast expansion of Waymo’s driverless car service is growing competition for Uber. The companies are also partners.

Uber is inviting customers to join an interest list if they want to ride in a Waymo robotaxi.

Uber is one step closer to letting customers hail a self-driving vehicle in Austin, Texas, through its app. The company on Wednesday opened up its interest list so that curious riders can declare their interest in potentially being matched with a Waymo robotaxi,