collaborators

10 papers

cs.LG2026

Reinforcement Learning for Code Optimization

Pierre Chambon, Kunhao Zheng, Juliette Decugis +2

RL for code correctness is now established: have the model generate a program, run it against hidden test cases, and reward solutions that pass. Extending this to code optimization…

cs.AI2026

ToE: A Hierarchical and Explainable Claim Verification Framework with Dynamic Multi-source Evidence Retrieval and Aggregation

Zhaoqi Wang, Zijian Zhang, Kun Zheng +4

The rapid spread of fake news poses increasing threats to information ecosystems, especially as AI-generated misinformation under Generative Engine Optimization (GEO) poisoning all…

cs.LG2026

Extrapolative Weight Averaging Reveals Correctness-Efficiency Frontiers in Code RL

Kunhao Zheng, Pierre Chambon, Juliette Decugis +4

Linear interpolation between fine-tuned checkpoints has been shown to trace the Pareto front between competing objectives, but whether extrapolative weight averaging can extend suc…

cs.SE2026

WybeCoder: Verified Imperative Code Generation

Fabian Gloeckle, Mantas Baksys, Darius Feher +5

Recent progress in large language models (LLMs) has substantially advanced automatic code generation and formal theorem proving, yet software verification has not seen comparable g…

cs.SE2025

CWM: An Open-Weights LLM for Research on Code Generation with World Models

FAIR CodeGen team, Jade Copet, Quentin Carbonneaux +48

We release Code World Model (CWM), a 32-billion-parameter open-weights LLM, to advance research on code generation with world models. To improve code understanding beyond what can…

cs.CL2025

Improving Diversity in Language Models: When Temperature Fails, Change the Loss

Alexandre Verine, Florian Le Bronnec, Kunhao Zheng +3

Increasing diversity in language models is a challenging yet essential objective. A common approach is to raise the decoding temperature. In this work, we investigate this approach…

cs.CL2025

The KoLMogorov Test: Compression by Code Generation

Ori Yoran, Kunhao Zheng, Fabian Gloeckle +3

Compression is at the heart of intelligence. A theoretically optimal way to compress any sequence of data is to find the shortest program that outputs that sequence and then halts.…

cs.LG2025

Soft Policy Optimization: Online Off-Policy RL for Sequence Models

Taco Cohen, David W. Zhang, Kunhao Zheng +3

RL-based post-training of language models is almost exclusively done using on-policy methods such as PPO. These methods cannot learn from arbitrary sequences such as those produced…

cs.LG2025

Optimizing Language Models for Inference Time Objectives using Reinforcement Learning

Yunhao Tang, Kunhao Zheng, Gabriel Synnaeve +1

In this work, we investigate the merits of explicitly optimizing for inference time algorithmic performance during model training. We show how optimizing for inference time perform…

cs.LG2025

PILAF: Optimal Human Preference Sampling for Reward Modeling

Yunzhen Feng, Ariel Kwiatkowski, Kunhao Zheng +2

As large language models increasingly drive real-world applications, aligning them with human values becomes paramount. Reinforcement Learning from Human Feedback (RLHF) has emerge…