Senior Data Scientist, Product

Role Description

The Firefox Data Science team partners with Product and Engineering to grow usage of our flagship product: Firefox, the privacy-minded web browser. Our work informs prioritization, investment decisions, and the long-term growth strategy across Firefox.

The Senior Data Scientist will lead analytical support for a feature area to drive measurable user growth by framing ambiguous questions, designing measurement strategies, and delivering insights that shape product decisions. They will also contribute to the team's forecasting and growth modeling efforts, helping translate statistical models into actionable growth strategies. This role emphasizes judgment, communication, and influence, supported by strong technical execution.

• Own the analytical success for a feature area by defining north-star metrics, building datasets, establishing measurement strategies, and driving data-driven decisions.
• Provide deep-dive and root-cause analyses to guide feature development, such as understanding what’s driving a metric change or opportunity sizing of new features.
• Design and analyze experiments to understand feature impact, user behavior, and causal relationships.
• Design measurement plans to evaluate new growth initiatives and validate assumptions over time.
• Contribute to the team's statistical forecasting models and help translate model outputs into actionable growth plans.
• Sit at the intersection between product, engineering, and leadership to advise, influence, support, and implement our product decisions.
• Cultivate a culture of measurement and advocate for strong analytical standards and methodologies across the organization.

Qualifications

• 6+ years of experience in data science, analytics, or applied quantitative analysis, with a track record of influencing business decisions through data.
• Advanced proficiency in SQL and Python for analysis, modeling, and validation.
• Background in experimentation (A/B testing) and causal inference for product development.
• Familiarity with time-series forecasting or statistical modeling techniques.
• Experience communicating models and findings to senior leadership and cross-functional partners.
• Ability to operate effectively in fast-paced environments with multiple viable options, delivering directional insights with clear rationale.

Requirements

• Commitment to our values:
• Welcoming differences
• Being relationship-minded
• Practicing responsible participation
• Having grit

Benefits

• Generous performance-based bonus plans to all eligible employees - we share in our success as one team.
• Rich medical, dental, and vision coverage.
• Generous retirement contributions with 100% immediate vesting (regardless of whether you contribute).
• Quarterly all-company wellness days where everyone takes a pause together.
• Country specific holidays plus a day off for your birthday.
• One-time home office stipend.
• Annual professional development budget.
• Quarterly well-being stipend.
• Considerable paid parental leave.
• Employee referral bonus program.
• Other benefits (life/AD&D, disability, EAP, etc. varies by country).