Lead Data Scientist

Lead Data Scientist
Location: Midlands based HQ with weekly on-site presence
Salary: Up to £75,000 plus competitive bonus and benefits

A large UK consumer eCommerce business is scaling a new internal advertising and monetisation platform and is hiring a Lead Data Scientist to take technical ownership of its core algorithms.
This is a technical leadership role with end-to-end ownership of the algorithm roadmap. You will set direction, make architectural decisions, and lead delivery from experimentation through to production in a high-scale environment.

What you will do

• Own the technical and algorithm roadmap for a large-scale internal ads platform.
• Design, test and deploy advanced predictive and ranking models such as Two-Tower architectures, RNNs and learning-to-rank approaches.
• Lead architecture, model selection and production design decisions.
• Improve feedback loops to increase responsiveness to real-world events and outcomes.
• Set best practices for production ML, testing, monitoring and deployment.
• Act as the technical authority for data science across the ads domain.
• Work closely with engineering, product and commercial teams.
• Present outcomes and recommendations to senior stakeholders in clear business terms.

What you bring

• Strong background in data science applied to personalisation, recommendations or ranking problems.
• Proven experience owning and delivering production machine learning systems.
• Advanced hands-on experience with PyTorch or TensorFlow.
• Strong Python and SQL skills with experience in distributed processing such as PySpark.
• Comfortable making technical trade-offs in complex, ambiguous environments.
• Able to translate complex technical work into commercial impact.

Nice to have

• Experience in AdTech or monetisation systems.
• Familiarity with MLflow, Databricks and modern DevOps tooling.
• Experience working in large-scale consumer or eCommerce environments.

Working style and benefits

• Weekly on-site presence with flexible working.
• Competitive base salary with annual performance bonus
• Sharesave scheme.
• Private medical insurance.
• Pension contribution.
• 25 days holiday plus bank holidays with buy and sell options.
• Staff discounts.
• Subsidised food and on-site facilities.
• Gym discounts.
• Digital GP service and wellbeing support.

Why join

You will be joining a business operating at national and international scale, investing heavily in applied machine learning that directly impacts revenue.
This is not a research role. Your work will be put into production, used at scale, and you will be accountable for its impact.