RACES

RACES framework enables recursive composition of verifiable RL environments for LLM reasoning generalization

RACES (Recursive Automated Composition for Environment Scaling) is a new framework that treats verifiable RL training environments as composable building blocks, automatically fusing them when input/output types match. The system implements 300 base environments and four composition operators (SEQUENTIAL, PARALLEL, SORT, SELECT) to generate diverse reasoning patterns at scale. Experiments show consistent gains on unseen benchmarks: DeepSeek-R1-Distill-Qwen-14B improves from 48.2 to 51.3 and Qwen3-14B from 58.8 to 61.1 averaged across six benchmarks. Notably, RACES achieves parity with 300 individual environments using only 50 base environments, suggesting strong efficiency gains over linear environment scaling.