Calyptus

Data engineer for recommendation systems

In short

This is an individual-contributor data engineering role designing and owning the data architecture behind a consumer platform's recommendation and personalization systems, working closely with an AI Engineer. It's an onsite, full-time position in London at a pre-Series B startup, requiring hands-on data architecture experience and prior work supporting production ML or recommendation systems. The company wants someone comfortable in a small, in-office team who stays hands-on rather than moving into a lead role.

About the role
This is the foundation role for our intelligence layer. You'll design and build the data architecture that the company's recommendation and personalization work runs on — partnering directly with the AI Engineer who builds the algorithms. They design the model; you make sure the data is there, clean, fast and structured to support it. This is deliberately an individual contributor role, not a lead. We're looking for someone who wants to build.
Responsibilities
•Design, build and own the data architecture behind a consumer platform
•Build reliable, performant pipelines that feed production ML and personalisation systems
•Model data so it's genuinely usable — by algorithms and by people
•Work hand-in-hand with the AI Engineer to get the right signals into the right shape
•Make pragmatic architecture decisions in a fast-moving, pre-Series B environment
Requirements
•Mid-senior Data Engineer with intimate, hands-on knowledge of data architecture — you've made the design decisions, not just implemented someone else's
•Experience supporting production ML or recommendation systems with the data underneath them
•A strong individual contributor who wants to stay hands-on
•AI-native: you use modern AI tooling as a genuine multiplier on your own work
•Comfortable in a small, in-office team where you'll see the impact of your work immediately
Nice to have
•Background in travel or a comparable high-volume consumer platform (e.g. TripAdvisor, Booking, Expedia)
•Experience at a company that scaled through Series B to C/D/E
Conditions
No conditions stated in the posting.

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