Lead Data Scientist – Hybrid

About the client

Our client is a global technology company operating in the online marketplace sector. With offices across Europe and North America, they are known for building innovative platforms that connect communities and enhance everyday experiences. The company values collaboration, diversity, and continuous learning, offering employees the chance to contribute to impactful projects in a dynamic and supportive environment.

We are seeking a Lead Data Scientist to join the data science and analytics division in Barcelona. This role involves driving advanced machine learning initiatives, leading cross-functional projects, and mentoring junior data scientists. The focus is on solving marketplace challenges such as search optimization, ranking algorithms, and personalized recommendations, making this a unique opportunity for professionals eager to combine leadership responsibilities with technical expertise.

This is a hybrid position requiring two days per week in the Barcelona office.

• Position: Senior Data Scientist – Hybrid – Barcelona
• Type of work: Hybrid from Barcelona.
• Work from office requirements: 2 days per week in the Barcelona office. 100% remote option is not available.
• Type of contract: Full-time employment contract.
• Contract location: Spain.
• Type of company: A fast-growing tech company connecting users with trusted providers worldwide — making everyday care easier, safer, and more accessible while creating a meaningful impact in millions of lives.
• Years of experience required: 6+ years of experience, 1+ year of lead experience
• Must-have tech skills: SQL, Python, common data science libraries, data visualization, and a strong foundation in statistics and machine learning.
• Industry: On-Demand Consumer Services/ Gig Economy Tech.
• Relocation support: Relocation support for EU expats.
• Bonuses, perks, benefits: Competitive compensation package with performance-based incentives, permanent contract with a pension plan, meal tickets, private health insurance, generous PTO allowance, flexible work hours + relocation assistance if needed, life insurance, wellness/gym membership options
• Reasons why it is a great place to work? It is a mission-driven, fast-growing tech company that makes a real impact worldwide. It offers a diverse, collaborative culture with strong leadership, flexible work options, relocation support, and competitive benefits. Employees enjoy access to cutting-edge technology, continuous learning, and a focus on well-being, recognition, and social responsibility.
• Work permit requirements: Only candidates with a valid work permit for any European Union (EU) country will be considered for this role.

• SQL

• Python (pandas, numpy, scipy, scikit-learn, xgboost)

• Data visualization (Tableau, Mode, Matplotlib, ggplot, or similar)

• Big data tools (AWS, Spark, Redshift)

• Lead large-scale data science projects in collaboration with product, engineering, and operations teams.

• Guide the evolution of search and recommendation algorithms by incorporating new features and optimization strategies.

• Mentor and support junior data scientists, ensuring high-quality output and professional growth within the team.

• Conduct in-depth analysis of marketplace dynamics, delivering actionable insights and strategic recommendations.

• Design, build, and maintain reliable data pipelines that power decision-making and model deployment.

• Implement and promote best practices in machine learning development, monitoring, and performance evaluation.

• Apply statistical methods to predict user behavior, assess interventions, and derive causal insights when experiments are not possible.

• At least 6 years of experience as a Data Scientist in a business environment, including 1+ years mentoring or managing others.

• A degree in a quantitative discipline; advanced degrees (MS or PhD) are highly valued.

• Strong expertise in probability, statistics, and experimental design.

• Hands-on experience with modern machine learning algorithms such as ensemble models, NLP, clustering, or deep learning.

• Proven success working with Search, Ranking, and Recommendation systems.

• Excellent SQL and…