Senior Data Scientist

We are seeking a driven and pragmatic Senior Data Scientist to join our Data Science Research team on a 1.5-year temporary contract as a parental leave replacement. This hybrid role combines team leadership with hands-on technical contributions. You will lead a group of skilled engineers and data scientists, collaborate with cross-functional stakeholders, and ensure the successful delivery of impactful, high-quality solutions.

If you’re:

Proactive - always seeking a satisfying solution to unexplored questions

Open-minded - happy to give & receive feedback, not afraid to fail and move on

Persistent - exhibit the skills and attitude to lead a project to success as well as how to extract yourself from common pitfalls

Creative - researching and developing a solution to challenging problems with large datasets

We want to talk to you.

1.5-Year Contract (Maternity Leave Coverage)

Key Responsiebilities

• Lead a team of data scientists and engineers in delivering high-quality insights, products and services with measurable business impact.

• Own the methodology that powers OpenX’s experimentation framework, and the analysis of experimental results

• Act as a proactive driver keeping projects moving forward, focusing on solutions over obstacles, and maintaining momentum even in uncertain situations.

• Prioritize team workload effectively, make thoughtful trade-offs, and balance excellence with practicality recognizing when "good enough" is sufficient.

• Mentor, coach, and guide data scientists by helping them set career goals and chart actionable development plans.

• Onboard new team members and cultivate a collaborative, inclusive, and high-performing team culture.

• Work closely with stakeholders across the business to align on priorities, share progress transparently, and ensure ongoing communication.

• Partner with business teams to align technical priorities with strategic goals and ensure measurable outcomes.

  
  

Required Qualifications

• 5+ years of experience in data science, with a strong technical foundation.

• 1+ year of experience leading data science teams or technical projects.

• Demonstrated ability to prioritize effectively, delegate tasks, and manage competing demands.

• Excellent communication, leadership, presentation, and collaboration skills.

• Proficient in Python and SQL

• Hands on experience on experiment design (A/B and Switchback) and causal inference techniques

• Deep understanding of probability and statistics, with experience applying methods at scale.

• Bachelor’s degree in Statistics, Mathematics or equivalent practical experience

• Working proficiency in both Polish and English.

  
  

Desired Characteristics

• Experience mentoring and guiding junior team members.

• Strong decision-making skills with a pragmatic mindset and ability to avoid over-engineering.

• Hands-on experience with cloud platforms, especially Google Cloud Platform (GCP)

• Background in digital media, marketing technology, or advertising technology industries.