1/ muse spark open is the most capable US open-weight model to date.
816B total params, 42B active. 1M-token context. natively multimodal. built for coding and agentic work like long-horizon tasks, hard software engineering, multi-step reasoning.
america! 🇺🇲
Alexandr Wang
@alexandr_wang
2/ read more on our blog here:
research.meta.ai/blog/muse-spar…
research.meta.ai/blog/muse-spar…
research.meta.ai
Introducing Muse Spark Open, The Most Capable US Open‑Weight Model to Date
Muse Spark Open is the most capable US open-weight model to date, and brings leading agentic capabilities to your desktop on Apple M5 Ultra Mac Studios.
5:04 PM UTC · Oct 15, 2026 · 33.6K Views
62529356
Alexandr Wang
@alexandr_wang
3/ muse spark open is available today through API platforms at Baseten, Fireworks AI, Groq, Modal, Nebius, OpenRouter and Together AI.
model weights are available for download on Amazon SageMaker AI, Google Cloud Model Garden, Hugging Face, and Microsoft Foundry Model Catalog.
it runs on leading inference engines like SGLang, vLLM, TensorRT-LLM, Hugging Face Transformers, Apple MLX, llama.cpp, and Unsloth with optimizations for AMD, Apple, Intel, and NVIDIA silicon.
developers can easily further customize the model using the PyTorch framework.
model weights are available for download on Amazon SageMaker AI, Google Cloud Model Garden, Hugging Face, and Microsoft Foundry Model Catalog.
it runs on leading inference engines like SGLang, vLLM, TensorRT-LLM, Hugging Face Transformers, Apple MLX, llama.cpp, and Unsloth with optimizations for AMD, Apple, Intel, and NVIDIA silicon.
developers can easily further customize the model using the PyTorch framework.
5:07 PM UTC · Oct 15, 2026 · 27.8K Views
141530642