Nemotron 3.5 Lightning pairs open weights with a pre-alpha model router
NVIDIA released Nemotron 3.5 Lightning, a 30-billion-parameter mixture-of-experts model that activates about 3 billion parameters, in BF16 and NVFP4 formats with training data and recipes. It also released NeMo Switchyard, a provider-agnostic SDK for routing agent requests among models and translating OpenAI- and Anthropic-style protocols.
Why it matters: The release combines a small active inference footprint with a routing layer intended to reserve expensive frontier models for the requests that need them.