← All roles

Research Engineer / Scientist, Post-training & Reinforcement Learning - London

H Company· Research
Apply on company site
Hybrid (Hybrid London)Full-timePosted 6mo ago

About the role

Research Engineer / Scientist focused on post-training and reinforcement learning for agentic AI, with hybrid work in London. Responsibilities span developing/training LLMs and VLMs, improving instruction following and tool use, and building scalable training pipelines, with collaboration across teams to deploy agentic systems.

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

Qualifications

  • Strong programming skills in Python, Rust, or similar; strong software engineering fundamentals
  • Proficient in deep learning frameworks (PyTorch, JAX, TensorFlow)
  • Experience training LLMs/VLMs with techniques such as SFT, DPO, RLHF/RLVR, reward modelling, offline RL, distillation
  • Experience with offline and online reinforcement learning in or outside of language models
  • Ability to work across training backends, data ingestion, ML/RL algorithm design and implementation
  • Strong research mindset with distributed computing experience

Skills

Required:PythonPyTorch / JAX / TensorFlowDistributed trainingRL from RLHF / RLVR / offline RL
Nice to have:Rust

Benefits

  • Highly competitive salary
  • Opportunities for professional growth and continuous learning
  • Collaborative, multicultural environment
Last updated Oct 8, 2026. Interested? Apply on the company site.

About H Company

H is an AI Research Lab and Product Company

H is an AI Research Lab and Product Company

AIProductResearchfrontier-labsheadline-ai-europe-100-2026liquid-ai-recruiting-target

More open roles at H Company