Senior AI Researcher - Post-Training for Enterprise Coding

Sonar; Greater London; On-site; GBP 110,000 - 150,000; Full time

Job summary

Sonar is seeking an ambitious senior researcher to join our cross-disciplinary team, innovating the next generation of enterprise-grade coding agents and models. You will leverage Sonar’s static analysis expertise and cutting-edge post-training techniques for large language models to deliver practical, high-impact solutions for customers, working hands-on with researchers and engineers.

This role demands clear communication to explain complex ideas and to translate research outcomes into shipped

Qualifications

• Advanced degree in Computer Science, ML, or a related field.
• 4+ years industry experience in machine learning with solid software engineering practices.
• Fluency with Python; experience with Rust or C/C++/JS/TS/Java is a plus.
• Expertise in post-training of large language models including PPO, RLVR, SFT, data-centric AI, PEFT and safety alignment.
• Experience driving research projects and translating findings into products; strong English communication.

Responsibilities

• Outcome Driven Development: develop and implement products that enable customers to post-train models for coding agents.
• Translate Prototypes to Products: collaborate with researchers and engineers to design experiments and convert concepts into products.
• Subject Matter Expert: contribute and discuss ideas to advance coding model post-training for enterprises.
• Speahead Research & Innovation: stay up-to-date with LLM and agentic developments and explain complex ideas clearly.

Skills

Python for ML

Rust or C++

Post-training LLMs

Policy optimization (PPO/GRPO)

RL frameworks (RLVR)

Data-centric AI & synthetic data

PEFT

English communication

Education

Master's or PhD in Computer Science / ML

Job description

Sonar is seeking an ambitious senior researcher to join our cross-disciplinary team, innovating the next generation of enterprise-grade coding agents and models. You will leverage Sonar’s static analysis expertise and cutting-edge post-training techniques for large language models to deliver practical, high-impact solutions for customers, working hands-on with researchers and engineers.

This role demands clear communication to explain complex ideas and to translate research outcomes into shipped