Nemotron-Cascade 2: Post-Training LLMs with Cascade RL and Multi-Domain On-Policy Distillation

TL;DR

Nemotron-Cascade 2 is a compact open 30B MoE model that achieves top-tier reasoning and agentic skills, rivaling larger models in mathematical and coding tasks through innovative training and distillation techniques.

Contribution

The paper introduces multi-domain on-policy distillation and expanded Cascade RL, significantly enhancing reasoning capabilities of a compact LLM.

Findings

Achieves Gold Medal-level performance in IMO, IOI, and ICPC with 20x fewer parameters.

Approaches frontier open models in mathematical and coding reasoning.

Demonstrates high intelligence density in a compact model.

Abstract

We introduce Nemotron-Cascade 2, an open 30B MoE model with 3B activated parameters that delivers best-in-class reasoning and strong agentic capabilities. Despite its compact size, its mathematical and coding reasoning performance approaches that of frontier open models. It is the second open-weight LLM, after DeepSeekV3.2-Speciale-671B-A37B, to achieve Gold Medal-level performance in the 2025 International Mathematical Olympiad (IMO), the International Olympiad in Informatics (IOI), and the ICPC World Finals, demonstrating remarkably high intelligence density with 20x fewer parameters. In contrast to Nemotron-Cascade 1, the key technical advancements are as follows. After SFT on a meticulously curated dataset, we substantially expand Cascade RL to cover a much broader spectrum of reasoning and agentic domains. Furthermore, we introduce multi-domain on-policy distillation from the strongest intermediate teacher models for each domain throughout the Cascade RL process, allowing us to efficiently recover benchmark regressions and sustain strong performance gains along the way. We release the collection of model checkpoint and training data.