The Tesla semi isn’t due to go into production until 2019, but there are already prototypes of the electric truck on the road in California.

A recent report reveals the Semi has moved beyond brief excursions around the company’s Bay Area (SanFrancisco) factory and has ventured onto the highway — and that this foreshadows its first regular route for the truck’s first official customer.

As Electrek reported recently, that customer would be Tesla itself.

The truck was spotted on a highway outside Sacramento, which is roughly midway between the Tesla assembly facility north of San Jose and the Gigafactory located just east of Reno, Nevada.

Tesla executive Jerome Guillen said last year that the trucks would be used to carry materials between the two sites, though Tesla founder Elon Musk has since suggested the company could eventually build a hyperloop

The Tesla Semi seems like a smart, short-term bet, at the very least.