Senior Data Scientist, Personalisation & Recommender Systems

Relay; Greater London; Hybrid; GBP 90,000 - 130,000; Full time

Job summary

Relay is seeking a Senior Data Scientist in London to shape the future of our recommender systems. You will own end-to-end model development, from research to production, balancing user and courier requirements with scalable optimisation.

You bring deep expertise in recommender systems, reinforcement learning and LLMs, and thrive in an environment that values experiments, rapid iteration, and evidence-based decisions. Join an intellectually vibrant, growth-focused team.

Qualifications

• Experience building recommender systems at scale and taking them to production.
• Deep expertise in reinforcement learning and large language models.
• Strong experimental mindset with data-driven decision making.

Responsibilities

• Define and drive the recommender strategy and roadmap for production systems.
• Lead end-to-end design, development and deployment of recommender models.
• Collaborate with OR to unite recommender models with optimisation.
• Contribute to the company’s research culture and community presence.

Skills

Recommender systems

Reinforcement learning

LLMs

Experimentation

Education

PhD in CS/Math/OR

Job description

Relay is seeking a Senior Data Scientist in London to shape the future of our recommender systems. You will own end-to-end model development, from research to production, balancing user and courier requirements with scalable optimisation.

You bring deep expertise in recommender systems, reinforcement learning and LLMs, and thrive in an environment that values experiments, rapid iteration, and evidence-based decisions. Join an intellectually vibrant, growth-focused team.