Boston-based self-driving startup Optimus Ride said on Thursday that it will provide rides in its golf cart-sized vehicles to tenants of a $1.4 billion mixed-use development project in Reston, Virginia, starting later this year. It will be a very modest deployment of the technology — three vehicles on a fixed loop to and from the parking facility — but it underscores the need for self-driving car operators to rein in their ambitions before going public.

An MIT spinoff, Optimus Ride said its vehicles would be confined to the private development site called Halley Rise, and it will be geofenced, meaning they can’t operate outside of a specific geographic area. Human safety drivers will be in each vehicle in case anything goes wrong, though the company claims its technology is Level 4 capable, or able to handle all of the driving duties within the geofence and under specific conditions. The vehicles won’t exceed 30 mph.

The vehicles won’t exceed 30 mph

Optimus Ride’s robot taxi service is the result of a deal struck with real estate giant Brookfield Properties, which owns numerous commercial and residential sites across the globe. If all goes well, Optimus Ride will deploy autonomous vehicles in other Brookfield-owned properties in the future. Halley Rise, a new $1.4 billion mixed-use district, will transform a 36-acre office park in Reston into 3.5 million square feet of housing, retail, offices, public green spaces, and year-round cultural activities. It is also the future home of a Wegmans Food Market in Fairfax County.

The deployment calls to mind similar services that are available through the startup Voyage in retirement communities in California and Florida, or Drive.ai in Frisco, Texas: they’re low-speed autonomous vehicles in tightly controlled areas with an operations team that constantly monitors them.

As billion-dollar companies like Alphabet’s Waymo, Uber, Ford, and GM Cruise scramble to perfect their high-profile robot taxi projects before they launch, smaller, more nimble startups are making progress in lower-stakes pilots that are operating right under our noses. In addition to Voyage and Drive.ai, companies like May Mobility, Udelv, and Nuro are operating their weird-looking, slow-moving autonomous vehicles on public roads right now.

Robot-taxi services in dense, urban environments are immensely complicated, and even companies that are the furthest along in the technology, like Waymo and GM, have struggled to develop self-driving vehicles that can navigate tricky traffic scenarios safely and without endangering or annoying pedestrians and other drivers on the road.

Optimus Ride won’t be the first company to bring its self-driving cars to the Washington, DC area, however: Ford-backed Argo.ai intends to begin testing its autonomous vehicles in the nation’s capital this year.