NVIDIA debuts Nemotron 3.5 Lightning as first open model

Nvidia released Nemotron 3.5 Lightning, a 30-billion-parameter open mixture-of-experts model, alongside NeMo Switchyard, an open-source library that directs each step of an AI workflow to the most appropriate model available. What Nemotron 3.5 Lightning actually does The model uses a mixture-of-experts architecture, which means that while it has 30 billion total parameters, only about 3 billion are active at any given moment. This design makes Nemotron 3.5 Lightning particularly suited for high-volume, specialized agent tasks. The kinds of operations that enterprises run thousands of times per day, like document parsing, data extraction, or customer query classification, don’t need frontier-scale reasoning. Nemotron 3.5 Lightning extends a model family that has been growing steadily since late 2025, when Nvidia rolled out variants including Nano, Super, and Ultra. Each targets a different slice of the performance-cost spectrum, and Lightning slots in as the option optimized for agentic workloads that need to run cheaply at massive scale. NeMo Switchyard: the traffic controller NeMo Switchyard is an open-source Rust library, now available on GitHub, that handles LLM traffic routing ...