Technical Lead — Data Science (f/m/x)

Sii is looking for a Technical Lead in Data Science to guide teams in delivering high-impact, production-ready solutions. You will own the technical direction of projects, mentor team members, and remain hands-on with code while ensuring that modeling approaches meet rigorous standards.

Key responsibilities

• Own the technical direction of data science engagements, including solution design, modeling, and delivery quality.
• Lead and mentor a team of data scientists through code reviews, methodology guidance, and career development.
• Stay hands-on by prototyping approaches, unblocking the team on complex problems, and contributing production-grade Python code.
• Translate client business problems into scoped workstreams and enforce engineering standards like reproducibility and testing.
• Represent the team in front of clients, defend methodologies, and manage technical expectations.

Requirements

• At least 6 years of experience in data science with a proven track record of shipping models to production.
• Minimum 2 years of experience leading or mentoring other data scientists.
• Deep, hands-on Python skills and strong foundations in statistics and machine learning.
• Familiarity with at least one major cloud or data platform such as Azure, AWS, GCP, Snowflake, Databricks, or Palantir.
• Strong communication skills with the ability to explain technical concepts to non-technical stakeholders.
• Fluent in both English and Polish, with residency in Poland.

What we offer

• Access to an AI Grant program with dedicated budget and resources to build your own AI projects.
• Opportunity to work within an AI Center of Excellence alongside specialists in agentic, generative, and discriminative AI.
• Full access to modern AI-powered development tools like Claude, Cursor, and GitHub Copilot.
• Support for professional growth, including conference attendance, speaking opportunities, and a comprehensive benefits package.