Meta announced the Muse Spark Open AI model today, claiming that it’s the “most capable US open-weight model to date.” But the company also says that it’s the “the first model in its class” that can “run on your desktop using two Apple M5 Ultra Mac Studios with the latest MLX framework.”

Meta and Apple, typically rivals, worked together on the launch and are publicly supporting each other.

“Muse Spark Open — weights releasing today — runs great on new Mac Studios thanks to work with @johnternus and Apple,” Meta CEO Mark Zuckerberg said on X.

“Congrats to the team!” new Apple CEO John Ternus said in a reply. “Amazing to run a model of Muse Spark Open’s caliber and scale this efficiently, right from your desk. Mac Studio keeps pushing the boundaries of on-device AI!”

“We’re excited for mommy and daddy to be playing nice again,” Meta chief AI officer Alexandr Wang said to Axios, who also noted that the companies have been collaborating over several months.

The new model is a “natively multimodal model” with 816 billion total parameters that “excels at long-horizon tasks, complex software engineering, and multi-step reasoning,” according to Meta. Apple also published a new technical post about MLX, an “array framework” for ML tasks on Apple Silicon, Muse Spark Open, and two other open models.