DETROIT (Reuters) -Amazon's ( AMZN ) deal with Stellantis ( STLA ) to create in-car software that the companies hoped would transform the driving experience while bolstering their vehicle-tech credentials is "winding down," the companies confirmed after a Reuters inquiry. 

The Stellantis SmartCockpit project, which would rely on Amazon's ( AMZN ) in-car technology, is the latest example of traditional automakers struggling to work with Silicon Valley to introduce more sophisticated vehicle software.

"Stellantis ( STLA ) remains a valuable partner for Amazon ( AMZN ) , and the companies continue to work together on a range of initiatives," the companies said in a statement, adding that the decision to end their joint work on SmartCockpit was mutual.

The project between the Seattle tech giant and the maker of Jeeps, Peugeots and Alfa Romeos  was hailed by the CEOs of both companies when it was announced in 2022. The two planned to develop features that would make the cars feel like an extension of home by detecting the driver and personalizing settings such as the thermostat, navigation and even home automation, like turning on lights. 

Stellantis ( STLA ) had hoped Amazon's ( AMZN ) software expertise would help the global automaker in the race against companies like Tesla and China's BYD. And for Amazon ( AMZN ) it was meant to serve as a prototype for a wider rollout to more automakers.

In a January 2022 press release, Stellantis's ( STLA ) then-CEO Carlos Tavares said he hoped the partnership would help make the vehicles "the most wanted, most captivating place to be, even when not driving."

Tavares left the automaker abruptly last year, and the company is expected to name his replacement soon. Stellantis has since tried to revive its slumping stock, which fell about 40% in 2024, amid disappointing sales, especially in North America.

Automotive software has emerged as one of the most important, and difficult, areas for legacy automakers to nail. Much of what modern cars do today is dictated by code, including the feel of the brakes, infotainment system, and advanced driving-assistance features such as automated steering - for which automakers can charge subscription fees, unlocking significant revenue streams. Ford recently axed its next-generation electrical architecture due to ballooning costs around the technology. 

Reuters couldn't determine any singular reason the partnership on SmartCockpit ended. The companies said the shift "will allow each team to focus on solutions that provide value to our shared customers and better align with our evolving strategies."

Relative newcomers, like Elon Musk's Tesla, built electrical and software systems that can quickly deliver new features or fixes to customers at a lower cost to the company. Traditional carmakers, including Volkswagen and General Motors, have struggled to master these systems on their own, and have been poaching talent from Silicon Valley or forming partnerships in an effort to reverse that trend. 

Unlike Tesla which has very little complexity across its smaller lineup of vehicles, Stellantis ( STLA ) manages dozens of models across 14 brands and a maze of global suppliers, increasing the challenges around implementing new software. 

SmartCockpit was initially planned to arrive in vehicles in late 2024 to early 2025. It was a part of what Stellantis ( STLA ) called its ABC platform, which included its electrical architecture, called STLA Brain, and Autodrive driver-assistance system. 

Under the agreement, Stellantis ( STLA ) would pay Amazon ( AMZN ) for access to the software in each car, as well as other maintenance fees. As envisioned, Amazon ( AMZN ) would pay Stellantis ( STLA ) incentive fees for things like drivers signing up for its music subscription service through the vehicles, two sources said. 

The automaker also partnered with Amazon ( AMZN ) to use the tech company's cloud business, called Amazon Web Services, to store and update data across its complex lineup. Stellantis ( STLA ) will continue to rely on AWS, the companies said, and Alexa will also still be available in some Stellantis vehicles. 

Stellantis ( STLA ) could potentially continue work on the SmartCockpit with another operating system as its base, such as Google's Android platform, people familiar with the matter said. Amazon ( AMZN ) hoped that the team's work, internally called Digital Cabin or "Project Quatro," would rival Google's Automotive Services, the standard Android-based operating system used by many automakers, one of the sources said. 

Most of Amazon's ( AMZN ) Digital Cabin staff has been reassigned or left the company, one of the people said.