Senior Data Scientist

WHO WE ARE

At Macadam, we've built an app that rewards people for walking. With over 15 million users worldwide, we help individuals turn their daily steps into positive habits for health, wellbeing, and sustainability.

Our team is growing fast, and our ambitions are global. We operate at the intersection of health, gamification, and technology, and we're building a world-class data team to support this growth.

If you’re passionate about using data and machine learning to build products that improve lives at scale, we’d love to meet you.

Please submit your CV in English.

THE ROLE

We are looking for a Senior Data Scientist to help shape Macadam’s product and growth strategy through machine learning, experimentation, and advanced analytics.

You will work on high-impact topics such as personalization, user engagement, retention, monetization, fraud prevention, and reward economy optimization. This is a hands-on senior role with ownership from problem definition through deployment and impact measurement.

You will partner closely with Product, Growth, Marketing, Engineering, and Analytics teams to build data-driven solutions used by millions of users.

This role is based in Barcelona. We're looking for candidates who are already living in the city or ready to relocate.

RESPONSIBILITIES

• Identify and lead data science opportunities that improve growth, engagement, retention, revenue, and user experience
• Build machine learning models for personalization, recommendations, user behavior prediction, segmentation, and forecasting
• Develop solutions supporting churn prevention, lifetime value optimization, fraud detection, and Macadam’s reward economy
• Design and analyze experiments using A/B testing, causal inference, and other advanced statistical methods
• Take models from initial exploration to production, working closely with Data and Engineering teams
• Define clear success metrics and evaluate solutions based on measurable product and business impact
• Communicate findings and recommendations clearly to technical and non-technical stakeholders
• Contribute to Macadam’s data science roadmap, standards, and best practices

WHAT YOU'LL BRING

• 5+ years of experience in Data Science, Machine Learning, Applied Science, or a similar role
• Strong proficiency in Python and SQL
• Experience using BigQuery, GCP, dbt, and product analytics tools such as Mixpanel or Firebase Analytics
• Experience developing, deploying, and evaluating machine learning models
• Familiarity with data pipelines and production machine learning workflows
• Strong knowledge of statistical modeling, experimentation, and model evaluation
• Experience working with large behavioral, transactional, or product datasets
• Strong product and business mindset, with a focus on measurable outcomes
• Excellent communication and cross-functional collaboration skills
• Fluent in English

NICE TO HAVE

• Experience with consumer mobile apps, gaming, advertising, loyalty, or rewards products
• Experience with recommender systems, personalization, churn, LTV, or fraud models
• Experience with causal inference, uplift modeling, or large-scale experimentation
• Familiarity with mobile attribution frameworks, including Apple’s SKAdNetwork

WHAT'S IN IT FOR YOU

• Be part of a mission-driven company making a tangible difference in people's lives, one step at a time.
• Real ownership: lead high-impact data science initiatives and build solutions used by millions from day one.
• Opportunities for professional growth, learning, and international exposure.
• A supportive, talented, and passionate international team.
• Offices in the heart of Barcelona.
• Meal voucher.
• Wellness allowance (powered by Urban Sports).
• Private healthcare (Alan).
• Hybrid working culture with international flexibility.
• 4 additional Macadam holiday days.
• Friday team lunch.
• Company events and offsites.

WHY MACADAM?

We don’t just talk about change - we walk it.

Our principles:

• Make it happen - take ownership, drive outcomes that matter.
• Build together, win together - support and challenge each other to go further.
• Trust the data - decide clearly, act confidently, measure what counts.
• Build for people - design with empathy, simplicity, real humans in mind.
• Think bigger - set the bar high, push boundaries, imagine better ways.