Meta open-sources Muse Spark Open: 816B-parameter model that runs locally on two Mac Studios
gabriberton · x · 2026-10-16
Meta has released the weights for Muse Spark Open, billed as the most capable US open-weight model to date.
- Specs: 816B total parameters (42B active), natively multimodal, 1M-token context window
- Focus: Built for coding and agentic work — long-horizon tasks, complex software engineering, multi-step reasoning
- Desktop deployment: First model in its class to run locally on two Apple M5 Ultra Mac Studios via the latest MLX framework (each machine offers up to 512GB unified memory for the GPU)
- Availability: API access via Baseten, Fireworks AI, Groq, Modal, Nebius, OpenRouter, and Together AI; weights on Hugging Face, Amazon SageMaker, Google Cloud Model Garden, and Microsoft Foundry
- Inference: Supports SGLang, vLLM, TensorRT-LLM, llama.cpp, Apple MLX, and Unsloth, optimized for AMD, Apple, Intel, and NVIDIA silicon
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