Leandro von Werra

Researcher, Research, Hugging Face

Joined

June 2022

Names

Leandro von Werra (Preferred)

Leandro Von Werra

Emails

****@huggingface.co (Confirmed)

Personal Links

Career & Education History

Researcher

Research, Hugging Face (hf.co)

2021 – Present

MS student

Physics, ETHZ - ETH Zurich (ethz.ch)

2016 – 2018

Advisors, Relations & Conflicts

Coworker

Andrés Marafioti

2024 – 2025

Coworker

Thomas Wolf

2021 – 2025

Coworker

Lewis Tunstall

2021 – 2025

Expertise

Agents

2024 – 2025

NLP

2020 – 2025

LLM

2020 – 2025

Publications

BigCodeArena: Unveiling More Reliable Human Preferences in Code Generation via Execution
Terry Yue Zhuo, Xiaolong Jin, Hange Liu, Juyong Jiang, Tianyang Liu, Chen GONG, Bhupesh Bishnoi, Vaisakhi Mishra, Marek Suppa, Noah Ziems, Saiteja Utpala, Ming Xu, Guangyu Song, Kaixin Li, Yuhan Cao, Bo Liu, Zheng Liu, Sabina Abdurakhmanova, Wenhao Yu, Mengzhao Jia et al. (20 additional authors not shown)
- ICLR 2026 Conference Withdrawn Submission
- Readers: Everyone
DABstep: Data Agent Benchmark for Multi-step Reasoning
Alexander David Egg, Martin Iglesias Goyanes, Andreu Mora, Friso H. Kingma, Thomas Wolf, Leandro Von Werra
- Submitted to NeurIPS 2025 Datasets and Benchmarks Track
- Readers: Everyone
FineWeb2: One Pipeline to Scale Them All — Adapting Pre-Training Data Processing to Every Language
Guilherme Penedo, Hynek Kydlíček, Vinko Sabolčec, Bettina Messmer, Negar Foroutan, Amir Hossein Kargaran, Colin Raffel, Martin Jaggi, Leandro Von Werra, Thomas Wolf
- COLM 2025
- Readers: Everyone
SmolLM2: When Smol Goes Big — Data-Centric Training of a Fully Open Small Language Model
Loubna Ben allal, Anton Lozhkov, Elie Bakouch, Gabriel Martin Blazquez, Guilherme Penedo, Lewis Tunstall, Andrés Marafioti, Agustín Piqueres Lajarín, Hynek Kydlíček, Vaibhav Srivastav, Joshua Lochner, Caleb Fahlgren, Xuan Son NGUYEN, Ben Burtenshaw, Clémentine Fourrier, Haojun Zhao, Hugo Larcher, Mathieu Morlon, Cyril Zakka, Colin Raffel et al. (2 additional authors not shown)
- COLM 2025
- Readers: Everyone
SmolVLM: Redefining small and efficient multimodal models
Andrés Marafioti, Orr Zohar, Miquel Farré, Merve noyan, Elie Bakouch, Pedro Manuel Cuenca Jiménez, Cyril Zakka, Loubna Ben allal, Anton Lozhkov, Nouamane Tazi, Vaibhav Srivastav, Joshua Lochner, Hugo Larcher, Mathieu Morlon, Lewis Tunstall, Leandro Von Werra, Thomas Wolf
- COLM 2025
- Readers: Everyone
Parameter-Efficient Instruction Tuning Code Large Language Models: An Empirical Study
Terry Yue Zhuo, Armel Randy Zebaze, Leandro Von Werra, Harm de Vries, Qian Liu, Niklas Muennighoff
- DL4C @ ICLR 2025
- Readers: Everyone
SmolLM2: When Smol Goes Big - Data-Centric Training of a Small Language Model
Loubna Ben Allal, Anton Lozhkov, Elie Bakouch, Gabriel Martín Blázquez, Guilherme Penedo, Lewis Tunstall, Andrés Marafioti, Hynek Kydlícek, Agustín Piqueres Lajarín, Vaibhav Srivastav, Joshua Lochner, Caleb Fahlgren, Xuan-Son Nguyen, Clémentine Fourrier, Ben Burtenshaw, Hugo Larcher, Haojun Zhao, Cyril Zakka, Mathieu Morlon, Colin Raffel et al. (2 additional authors not shown)
- CoRR 2025
- Readers: Everyone
Towards Best Practices for Open Datasets for LLM Training
Stefan Baack, Stella Biderman, Kasia Odrozek, Aviya Skowron, Ayah Bdeir, Jillian Bommarito, Jennifer Ding, Maximilian Gahntz, Paul Keller, Pierre-Carl Langlais, Greg Lindahl, Sebastian Majstorovic, Nik Marda, Guilherme Penedo, Maarten Van Segbroeck, Jennifer Wang, Leandro von Werra, Mitchell Baker, Julie Belião, Kasia Chmielinski et al. (19 additional authors not shown)
- CoRR 2025
- Readers: Everyone
BigCodeBench: Benchmarking Code Generation with Diverse Function Calls and Complex Instructions
Terry Yue Zhuo, Vu Minh Chien, Jenny Chim, Han Hu, Wenhao Yu, Ratnadira Widyasari, Imam Nur Bani Yusuf, Haolan Zhan, Junda He, Indraneil Paul, Simon Brunner, Chen GONG, James Hoang, Armel Randy Zebaze, Xiaoheng Hong, Wen-Ding Li, Jean Kaddour, Ming Xu, Zhihan Zhang, Prateek Yadav et al. (13 additional authors not shown)
- ICLR 2025 Oral
- Readers: Everyone
Scaling Laws and Compute-Optimal Training Beyond Fixed Training Durations
Alexander Hägele, Elie Bakouch, Atli Kosson, Loubna Ben allal, Leandro Von Werra, Martin Jaggi
- ES-FoMo-II 2024 Poster
- Readers: Everyone

View all 45 publications

Co-Authors

View all 292 co-authors