Staff Machine Learning Scientist, Ranking

Depop is looking for a talented Staff ML Scientist to join our Ranking ML team in the UK. You will work alongside a cross-functional team of Product Managers, ML Engineers, and fellow ML Scientists, helping build and maintain ranking models to power Depop's app, serving millions of personalised results to users daily. As a staff-level member of the team, you will be expected to set the technical vision, lead high-impact initiatives, and mentor and coach others to drive innovation at scale, while working across multiple domains and stakeholders. Responsibilities You will:

• Lead the design and deployment of advanced ranking models for Depop's entire app, covering personalised recommendations, search results and other surfaces.
• Collaborate closely with cross-functional partners (product, engineering, data) to define problems, translate them into scalable solutions, and deliver measurable business outcomes.
• Lead the end-to-end lifecycle of ML projects: from ideation, data acquisition, feature engineering, training, and evaluation to deployment and ongoing iteration.
• Drive innovation in ranking by researching and integrating emerging ML techniques, frameworks, and tooling, while contributing technical expertise to long-term product and data strategy.
• Mentor, coach, and set technical direction within the Ranking ML team, helping others grow and innovate.
• Act as a thought leader in the ranking space, sharing learnings internally, engaging with the wider ML community, and showcasing our work externally.

• Significant experience working as a Machine Learning Scientist, with a proven track record of delivering and scaling models that solve complex, real-world problems with measurable business impact
• Proven track record in designing and optimizing learning-to-rank models
• Deep understanding of machine learning concepts and frameworks
• Proven ability to productionize ML models and pipelines: from prototyping to deployment, with strong experience in monitoring, iteration, and troubleshooting.
• Advanced programming skills in Python and familiarity with ML frameworks such as PyTorch, TensorFlow, or similar.
• Experience leading projects and mentoring engineers or scientists, with a track record of fostering team growth and technical excellence.
• Excellent communication skills: able to bridge technical and non-technical stakeholders and influence decision making.
• Committed to responsible AI practices, including attention to ethics, fairness, and inclusivity.

• PMI and cash plan healthcare access with Bupa
• Subsidised counselling and coaching with Self Space
• Cycle to Work scheme with options from Evans or the Green Commute Initiative
• Employee Assistance Programme (EAP) for 24/7 confidential support
• Mental Health First Aiders across the business for support and signposting

Work/Life Balance:

• 25 days annual leave with option to carry over up to 5 days
• 1 company-wide day off per quarter
• Impact hours: Up to 2 days additional paid leave per year for volunteering
• Fully paid 4 week sabbatical after completion of 5 years of consecutive service with Depop, to give you a chance to recharge or do something you love.
• Flexible Working: MyMode hybrid-working model with Flex, Office Based, and Remote options *role dependant
• All offices are dog-friendly
• Ability to work abroad for 4 weeks per year in UK tax treaty countries

Family Life:

• 18 weeks of paid parental leave for full-time regular employees
• IVF leave, shared parental leave, and paid emergency parent/carer leave

Learn + Grow:

• Budgets for conferences, learning subscriptions, and more
• Mentorship and programmes to upskill employees

Your Future:

• Life Insurance (financial compensation of 3x your salary)
• Pension matching up to 6% of qualifying earnings

Depop Extras:

• Employees enjoy free shipping on their Depop sales within the UK.
• Special milestones are celebrated with gifts and rewards!