We're looking for an experienced Staff Data Scientist, Experimentation to lead and evolve experimentation practices across the organization, drive statistical excellence, and support evidence-based product decisions.

🎯 Responsibilities

1. Define experimentation strategy, vision, and roadmap
2. Establish company-wide standards for experiment design, prioritization, guardrail metrics, and governance
3. Introduce and own advanced statistical methodologies (CUPED, sequential testing, network effect measurement, quasi-experimental designs, incrementality measurement)
4. Advise and coach Data Analysts, Data Scientists, and Product Managers on hypothesis development, experiment design, and success metrics
5. Build and deliver training programs, playbooks, and office hours for experimentation education
6. Collaborate with Data Engineering and Analytics Engineering to improve experimentation infrastructure and data practices
7. Develop experimentation approaches for marketplace features including search ranking, recommendations, personalization, supply-demand dynamics, trust & safety, seller growth, and monetization

🛠️ Requirements

1. 8+ years of experience in data science, product analytics, or causal inference, with at least 4 years deeply focused on experimentation (including experimental design, statistical inference, A/B testing, and variance reduction)
2. Strong proficiency in SQL and experience using Python or R
3. Proven ability to partner with Product teams and influence senior stakeholders using strong business judgment
4. Experience building experimentation cultures and coaching PMs and analysts
5. Excellent communication skills

➕ Nice to have

1. Experience with Amplitude
2. Background in marketplaces, e-commerce, consumer internet, or two-sided platforms
3. Experience with recommendation or search systems

🤗 We offer / Benefits

1. Generous individual learning budget (2K per year)
2. Free office meals with a variety of lunch options
3. Group and individual English, Catalan, and Spanish lessons during working hours
4. Private health insurance
5. Flexible working hours and intensive Fridays
6. Flexible remuneration options (kindergarten/food/transport checks)
7. Gym & wellness plan, including on-site physiotherapist
8. Referral program and charity donation initiatives
9. Bonuses for weddings and newborns
10. Support with tax income (Renta)
11. Monthly product advantages
12. Work anniversary gifts and birthday surprises
13. WIFI contribution in monthly payroll
14. One-off payment to support home office setup
15. Relocation package with monetary support and legal advice, plus visa sponsorship if needed
16. 26 holidays per year
17. Top hardware of your choice (latest Apple or Windows devices)

💼 Hiring Process

1. Intro call to discuss your background, motivation, and expectations
2. Technical task submission within 5-7 days to showcase expertise
3. Expertise interview focused on core skills and delivery ability
4. Stakeholder interview assessing collaboration in a cross-functional context
5. Culture interview focused on alignment with the organization's mission
6. Offer discussion and confirmation