Waymo, Alphabet’s self-driving car company, will work with ride-sharing service Lyft to develop new autonomous vehicle technologies. The two companies confirmed the partnership today, stating that they would work together on new self-driving products and pilots. But they stopped short of specifying exactly what they would be producing first or when details would be provided.

“We’re looking forward to working with Lyft to explore new self-driving products that will make our roads safer and transportation more accessible,” Waymo said in a statement. “Lyft’s vision and commitment to improving the way cities move will help Waymo’s self-driving technology reach more people, in more places.”

Not great news for Uber

Lyft’s own statement made similar promises. “We can confirm that we are partnering with Waymo to safely and responsibly launch self-driving vehicle pilots,” the company told The Verge. “Waymo holds today’s best self-driving technology, and collaborating with them will accelerate our shared vision of improving lives with the world’s best transportation.”

The idea of a partnership was originally seeded last summer, The New York Times reports, when Lyft founders Logan Green and John Zimmer sat down with Waymo CEO John Krafcik. Through visits to each others’ campuses, the conversation developed, resulting in the deal as announced today.

Zimmer is on record as saying that he expects the majority of his company’s rides will take place in self-driving cars by 2021, but the company has said that it has no plans to develop its own vehicles. Instead, it’s previously sought out similar partnerships with companies like General Motors, which invested $500 million into Lyft in 2015, two years before it tested its own autonomous Chevy Bolts on the streets of San Francisco.

The two companies haven’t announced what they’ll be working on

Waymo, meanwhile, has been testing the waters of ride-sharing by offering self-driving rides to residents of the Phoenix metropolitan area. A patent filed earlier this year — for technology that could determine pick-up and drop-off locations quickly and easily — also hinted at the company’s potential to make its own full-fledged ride-sharing network at some point in the future.

The new partnership may see Waymo and Lyft fold their current projects together, or continue with separate research tracks, but one thing is for sure — this announcement is not great news for Uber. Lyft is Uber’s biggest competitor in the ride-sharing market, while Waymo is currently embroiled in a legal battle with the company that may result in criminal charges leveled against Travis Kalanick’s company for theft of corporate secrets and a halt on its research.

Uber was already forced to admit that Waymo’s self-driving tech was ahead of its own, and now the company has to fight off its two biggest rivals on two fronts, while also dealing with its own internal problems and ongoing investigations. But while neither Lyft nor Waymo has announced concrete plans for their collaborative efforts, the current ride-sharing market leader still has a chance to maintain the advantage.