Senior Data Scientist

Company mission

In the future, almost everything we consume will simply materialise on our doorsteps – what we call “e-commerce” today will simply be “commerce” tomorrow. But if we continue on today’s trajectory, the growth of e-commerce risks damaging the environment, alienating our communities, and straining the bottom-line for small businesses.

Relay is an e-commerce-native logistics network built from the ground up for environmental, social, and economic sustainability. Our mission is to reduce the number of miles driven per parcel, lower carbon emissions, and reduce delivery costs — all while reinvesting into local communities.

About the role

As a highly operational business, we rely on data science to power every part of our network. From day one, we’ve built Relay around a deep understanding of our supply chain, using our best-in-class data assets to set strategy, improve quality, and optimise performance across every layer of the network. Our high-impact data team works across forecasting, optimisation, pricing, geospatial modelling, infrastructure planning, and more. Whether it’s planning courier capacity, guiding pitstop expansion, or improving the economics of delivery, our work directly shapes how Relay scales.

We are looking for Senior Data Scientists to join our growing data team; these are hands-on roles with wide scope and strong exposure to decision-making. You’ll partner closely with operations, product, and commercial teams to solve practical problems with real-world impact, often working from messy datasets and complex systems, where the answers don’t sit neatly in one model. You’ll be embedded in cross-functional teams, helping drive cost, quality, and reliability across the network. If you’re motivated by fast feedback loops, strong ownership, with strong exposure to leadership, and the chance to shape a growing system from the inside out, we’d love to hear from you.

Open Roles

Senior Data Scientist - Relay Network

The Network Data Science team is responsible for modelling, forecasting, and optimising how parcels, couriers, and costs flow through Relay’s delivery network. We work across the business to guide operational decisions, shape commercial strategy, and ensure the network scales sustainably. Example projects include:

• Forecasting parcel volumes at multiple horizons to inform hiring, shift allocation, pitstop scaling, and pricing

• Building operational and financial models to simulate trade-offs between cost, quality, and growth across the network

• Structuring fragmented datasets into usable insight using AI and programmatic approaches

• Embedding forecasting and planning models into live tooling used by operators, analysts, and finance teams

• Supporting strategic planning for new zone launches, infrastructure investment, and client expansion

• Acting as a thought partner to operations, commercial, and finance leads to bring a scientific lens to high-stakes planning and investment decisions

Senior Data Scientist - Attribution & Explainability

The Attribution & Explainability team acts as Relay’s internal detective squad, uncovering hidden inefficiencies, guiding smarter decisions, and driving meaningful impact across the business. Positioned at the centre of Relay’s operations, we partner with teams across logistics, finance, commercial, and beyond to bring clarity to complex problems and identify opportunities for improvement.

Our work helps illuminate which parts of the network are operating effectively and where bottlenecks, losses, or misalignments are occurring. Example projects include:

• Developing frameworks to identify where parcels are delayed or lost in the network, and designing interventions to resolve these bottlenecks

• Modelling the impact of future network expansion on operational constraints, helping to shape Relay’s long-term growth strategy

• Analysing marketplace dynamics to better understand the cost structures and incentives for last-mile couriers

• Collaborating with the broader data team to build forecasting models that inform high-level strategic planning

• Acting as a thought partner to operations, commercial, and finance leads, bringing a scientific, data-driven perspective to critical planning and investment decisions

You Will Thrive in This Role If You:

• 6+ years of experience in data science, with a strong record of delivering models into production

• Deep experience with Python and SQL

• Strong foundations in statistics and probability, with experience applying them in operational and/or financial contexts

• Comfort working in ambiguity and navigating messy or incomplete data

• Effective communication skills — you can explain technical results clearly to non-technical audiences

• Comfortable having strategic conversations with senior stakeholders, working across functions and disciplines to drive impact

Nice to haves

• Experience working in logistics, marketplaces, or similarly complex operational businesses

• Experience using LLMs or AI tools to structure and extract meaning from unstructured data

• Experience automating workflows and deploying model pipelines (e.g. MLFlow, GCP Vertex, Airflow, dbt or similar)

• Exposure to business planning, pricing, or commercial decision-making

• Familiarity with geospatial data

• Experience in fast-scaling startups or operational teams
  

We're flexible on experience – if you’re an experienced and pragmatic data scientist, with a track record of driving impact, we’d love to hear from you.

What Relay Offers:

• Generous equity package

• 25 days annual leave, plus bank holidays

• Bupa Global Business Premier health plan – including mental, dental, and optical cover

• Enhanced Parental Leave:

  • 20 weeks of fully paid maternity leave

  • 4 weeks of fully paid paternity leave

• Contributory pension scheme

• Friday office lunches

• Access to cutting-edge AI tooling

• Hybrid working from our dog-friendly Shoreditch office

• Free gym membership via our co-working spaces

• Cycle-to-work scheme

• Regular team socials, events, and offsites!!