Meta says its open Muse Spark model runs on two Mac Studios
Meta says its 816-billion-parameter open-weight model can run on two Apple M5 Ultra Mac Studios.
Meta released the weights for Muse Spark Open, which it calls “the most capable US open-weight model to date,” the company said Thursday in a blog post.
What it is: Muse Spark Open is a natively multimodal model with 816 billion total parameters, 42 billion of them active, and a 1 million-token context window, Meta said. The company says it is built for coding and agentic work, including long-horizon tasks, complex software engineering and multistep reasoning.
On a desktop: Meta says it is the first model in its class to run on a desktop using two Apple M5 Ultra Mac Studios with Apple’s MLX framework. Each Mac Studio’s GPU can use up to 512 GB of unified memory, so two machines can hold the entire model, according to the post. Mark Zuckerberg wrote on X that the model “runs great on new Mac Studios,” crediting work with Apple.
Where to get it: The weights are available on Amazon SageMaker AI, Google Cloud Model Garden, Hugging Face and Microsoft Foundry Models. Baseten, Fireworks AI, Groq, Modal, Nebius, OpenRouter and Together AI offer it through their APIs, Meta said. It is released under the Muse Model License “with limited commercial terms,” which Meta says lets many developers use it for free.
What’s next: Meta says a full evaluation report on the model’s safety testing will be available soon.
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