Senior Data Scientist

Company: Checkout.com
Apply for the Senior Data Scientist
Location: London
Job Description:

Overview

In this role you will lead advanced optimisation projects and shape scalable ML architectures to improve payment flows. You’ll work with a team of data scientists to design decisioning systems that balance complex business objectives. Expect to translate data insights into robust, production-ready models and collaborate with product partners to drive impact at scale. This is a fast-moving role with opportunities to influence fintech solutions and data-driven .

Pay / Benefits

  • hybrid working model
  • flexible in-office schedule (three days per week)
  • growth opportunities
  • collaborative culture
  • impactful work in fintech
  • global team exposure

Responsibilities

  • Lead projects and architecture design for multi-objective optimisation and scalable models
  • Create custom loss functions, evaluation, and tuning frameworks for complex business problems
  • Collaborate with product stakeholders to align technical strategy with business goals
  • Apply efficient data transformations using distributed computing (e.g., Spark, Dask) and ensure robust test coverage for production systems
  • Mentor junior team members and utilise model explainability methods to drive feature performance improvements

Key requirements

  • 5+ years of experience designing, building and maintaining ML models for large-scale problems
  • Deep understanding of frequentist and Bayesian statistics; supervised and unsupervised techniques
  • Experience modelling complex interactions (e.g., cluster or network effects)
  • Expertise in model explainability and feature engineering
  • Proficiency in high-quality production-grade Python code and cross-functional collaboration
  • Experience leveraging LLMs for coding support and process optimisation
  • Strong communication skills tailored to broad audiences
  • Proven ability to build trusting relationships with product stakeholders and understand business models
  • collaboration with cross-functional teams
  • mentoring junior members
  • clear technical communication
  • Spark
  • Dask
  • Python production-grade code

Posted: September 14th, 2026