Senior Data Scientist, Buyer

The Buyer Domain at Vinted is dedicated to creating a seamless, delightful, and highly engaging experience for our members as they search, discover, and purchase items. Our challenge is unique: unlike standard e-commerce, our peer-to-peer catalog consists of hundreds of millions of entirely unique, single-inventory listings, with millions of new items uploaded daily. Connecting the right buyer with the perfect item in real-time is at the very core of Vinted's success.

To tackle this challenge at scale, we are looking to bring talented Data Scientists into the Buyer Domain's two highly specialized, ML-focused teams:

• Build and optimize end-to-end machine learning models for retrieval, ranking, and personalization (e.g. gradient boosting, two-tower architectures, sequence models, and neural rerankers).
• Partner closely with platform and software engineers to serve models directly in our search and recommendation engines, optimizing for high throughput and millisecond-level latency budgets.
• Lead or contribute to collaborative design proposals for new modeling approaches, features, or training pipelines.
• Define tracking requirements, perform offline evaluations, and design and analyze online A/B tests to measure real-world business impact.
• Collaborate with Data, Engineering and Product stakeholders to identify product opportunities, translate business problems into ML objectives, and align on technical trade-offs.
• Share knowledge, participate in peer reviews, and actively contribute to the growth and development of other scientists in the ML Guild and the Data Science & Analytics function.

• A strong collaborator with hands-on experience designing, training, and deploying machine learning models in a production environment (ideally within search, recommendations, or large-scale personalization).
• High proficiency in Python and SQL. Experience with deep learning frameworks and gradient boosting libraries.
• Solid understanding of modern information retrieval, Learning-to-Rank (LTR), semantic search, or sequence-based user preference modeling.
• Experience or strong interest in high-performance model serving. Familiarity with search/vector engines like Vespa or Elasticsearch, and serving frameworks like Triton, is a plus.
• Comfort working with massive datasets in modern cloud-based data warehouses.
• Strong grasp of statistics, offline evaluation metrics, and online A/B testing methodologies.

• The opportunity to benefit from our share options programme
• 25 working days of holiday
• Access to all the tools & tech needed for work
• Home office support: we provide IT workstation equipment and a personal budget of up to 540 for home workplace furniture
• Private health insurance
• Digital mental and emotional health support and Employee Assistant Program (EAP)
• Frequent team-building events
• A personal monthly budget for shopping on Vinted
• The opportunity to spend up to 90 days per year - 21 of which can be spent working outside of the EU - on workation
• A dog-friendly office
• In Vilnius office: Gym & in-house meals at friendly prices
• In Kaunas office: a monthly lunch allowance, and a once-a-week provided in-house lunch and breakfast