# Research Engineer / Scientist, Post-training - Paris at H Company

> Open job at H Company in Paris, France. Workplace: Hybrid.

Source: France Dev Jobs, https://francedevjobs.com/jobs/h-company-research-engineer-scientist-post-training-paris-j4g7xcy
Posted 12 November 2025. Last checked on the employer's career site: 10 November 2026.

## Facts

- Company: [H Company](https://francedevjobs.com/companies/h-company)
- Location: Paris, France
- Workplace: Hybrid
- Employment type: Full-time
- French: Not required
- Skills: LLMs, PyTorch, Python, TensorFlow
- Not mentioned in the job post: salary, visa sponsorship, relocation, where you can apply from

## Job description

**About H:**
H exists to push the boundaries of superintelligence with agentic AI. By automating complex, multi-step tasks typically performed by humans, AI agents will help unlock full human potential.

H is hiring the world’s best AI talent, seeking those who are dedicated as much to building safely and responsibly as to advancing disruptive agentic capabilities. We promote a mindset of openness, learning, and collaboration, where everyone has something to contribute.

**About the Team:** The Models team builds the foundational models that power our cutting-edge agentic technology. We focus on training techniques to optimize model capabilities specifically for agent applications. This allows us to achieve the best performance at a given inference cost. Our work spans the development of Large Language Models (LLMs) and Vision-Language Models (VLMs), enabling agents to perceive, understand, and act within complex environments. We are deeply involved in enhancing these models through training methods with a focus on improved instruction following, tool use, and interaction with dynamic environments via large-scale reinforcement learning and reward modeling. We operate at the intersection of research and product, translating cutting-edge research into practical solutions that drive the next generation of AI. We are looking for bright, motivated individuals to join our ranks and shape the future of superintelligent AI.

**Key Responsibilities:**

- Develop and train advanced LLMs and VLMs, including multimodal architectures
- Research and implement training methods for enhanced capabilities like instruction following and tool use
- Design and optimize data pipelines and training systems for large-scale distributed training
- Collaborate with cross-functional teams to integrate models into agentic AI systems
- Evaluate model performance and communicate findings to stakeholders
- Stay current with advancements in LLMs, VLMs, and related fields

**Requirements:**

- Technical skills:
  - Strong programming skills (Python, Git)
  - Expertise in deep learning frameworks (PyTorch, JAX, TensorFlow)
  - Experience with large-scale distributed training of LLMs and VLMs
  - Hands-on experience with LLM training, alignment, and reinforcement learning
  - Knowledge of multimodal architectures and applications
- Research skills:
  - Publications in top-tier AI conferences (e.g., NeurIPS, ICML, CVPR, ACL, ICCV)
  - Advanced degree (PhD or MSc) in a relevant field (e.g., ML, DL, NLP, CV)
- Soft skills:
  - Excellent communication and presentation skills
  - Strong collaboration and teamwork skills
  - Passion for AI and problem-solving
- Bonuses:
  - Industry experience
  - Experience in LLM training with RL
  - Experience with data processing techniques

**Location:**

- Paris or London.
- This role is hybrid, and you are expected to be in the office 3 days a week on average.
- Please expect some travel between offices on a reasonable cadence (e.g., every 4-6 weeks).

**What We Offer:**

- Join the exciting journey of shaping the future of AI, and be part of the early days of one of the hottest AI startups
- Collaborate with a fun, dynamic and multicultural team, working alongside world-class AI talent in a highly collaborative environment
- Enjoy a competitive salary
- Unlock opportunities for professional growth, continuous learning, and career development

**If you want to change the status quo in AI, join us.**

## How to apply

Apply on the job page, https://francedevjobs.com/jobs/h-company-research-engineer-scientist-post-training-paris-j4g7xcy: its Apply button opens the employer's own application page.

## More jobs from H Company

- [Infrastructure Engineer (ML Compute) - London](https://francedevjobs.com/jobs/h-company-infrastructure-engineer-ml-systems-london-ku6jjue): H Company, Paris, France. Hybrid. Posted 12 October 2026.
- [Infrastructure Engineer (ML Compute) - Paris](https://francedevjobs.com/jobs/h-company-infrastructure-engineer-ml-systems-paris-zczrjdv): H Company, Paris, France. Hybrid. Posted 12 October 2026.
- [Product Designer - Paris](https://francedevjobs.com/jobs/h-company-product-designer-paris-d9lswwu): H Company, Paris, France. Hybrid. Posted 12 October 2026.
- [Product Designer - London](https://francedevjobs.com/jobs/h-company-product-designer-london-qwjctcd): H Company, Paris, France. Hybrid. Posted 12 October 2026.
- [Senior Full Stack Engineer](https://francedevjobs.com/jobs/h-company-senior-full-stack-engineer-1stg1ud): H Company, Paris, France. Hybrid. Posted 9 October 2026.