Site Lead, Data & ML (up to £240k)

Dex; Greater London; On-site; GBP 150,000 - 210,000; Full time

Job summary

Dex is partnering with a fast-growing European company building its first dedicated data and ML presence in London. You will lead from day one, remaining a true technical contributor while growing a team from one to ten in the next year.

The role focuses on reward optimisation, real-time personalisation, and offer ranking, with responsibilities spanning architecture, hiring, and high-impact delivery.

Qualifications

• Strong individual contributor background at senior, staff, or principal level.
• End-to-end ownership of an applied-ML domain: recommendation, ranking, marketplaces, adtech, or similar.
• Clear examples of business outcomes your technical work directly drove.
• Comfort defining solutions in ambiguous environments, rather than following existing playbooks.
• Experience hiring, coaching, and setting the technical bar for a small, high-ownership team.

Responsibilities

• Lead the London data and ML function, defining its roadmap and technical strategy.
• Drive applied ML initiatives across reward optimisation, real-time personalisation, and offer ranking.
• Build and scale a high-ownership team from scratch, setting the technical bar and interview process.
• Contribute technically through design reviews, code reviews, and model reviews.
• Translate business priorities into technical plans, ensuring direct impact on company-level outcomes.

Skills

Senior/Staff/Principal level

End-to-end ML ownership

Applied ML domain experience

Ambiguity handling

Hiring & coaching

Job description

This role is with one of Dex's trusted partner companies. We work closely with their teams to truly understand their culture, goals, and what they're looking for, so we can match you with the right opportunity and give you context about the role before you commit to a process.

Dex is an AI recruiter agent that helps you run your job search. Tell Dex your stack, seniority, and what you want to build. We will manage your applications and surface other opportunities that are a fit.

The role

This is a profitable, bootstrapped platform rewarding 80 million users globally. They're one of Europe's fastest-growing companies, building out their first dedicated data and ML presence in London.

You'll lead that function from day one, growing a team from a single hire to ten over the next year. This isn't a distant management role: you'll stay a genuine technical contributor, reviewing designs and code, joining model reviews, and staying in the problems. The work is applied and commercial: reward optimisation, real-time personalisation, offer ranking. You're building the ground the team will stand on, not just tuning something that already runs.

The work

• Lead the London data and ML function, defining its roadmap and technical strategy.
• Drive applied ML initiatives across reward optimisation, real-time personalisation, and offer ranking.
• Build and scale a high-ownership team from scratch, setting the technical bar and interview process.
• Contribute technically through design reviews, code reviews, and model reviews.
• Translate business priorities into technical plans, ensuring direct impact on company-level outcomes.

What You Bring

• Strong individual contributor background at senior, staff, or principal level; you want to keep building.
• End-to-end ownership of an applied-ML domain: recommendation, ranking, marketplaces, adtech, or similar.
• Clear examples of business outcomes your technical work directly drove.
• Comfort defining solutions in ambiguous environments, rather than following existing playbooks.
• Experience hiring, coaching, and setting the technical bar for a small, high-ownership team.

Why apply through Dex

This is a rare, foundational leadership role in a rapidly scaling, profitable business. Opportunities like this are often oversubscribed or hard to find.

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