Data Science Technical Lead – Hands-On & Mentoring

Sii Poland; Bydgoszcz; On-site; PLN 250,000 - 380,000; Full time

Benefits offered by this job

Great Place to Work

Centre of internal trainings

Profit sharing

Medical care

Office in Poland

Job summary

Sii Poland is seeking a technical lead to own end-to-end data science projects, framing problems with clients and signing off on modeling approaches. You will mentor a team, review work, and ensure production-grade Python delivery across platforms like Microsoft Fabric, Palantir Foundry, and Databricks.

You will stay hands-on while guiding standards, experimentation, and engineering practices. Fluent English and Polish are required, and you must reside in Poland.

Qualifications

• 6+ years in data science with production models and 2+ years leading others
• Deep Python skills across pandas, NumPy, scikit-learn, XGBoost
• Fluent English and Polish; residing in Poland

Responsibilities

• Own the technical direction of data science engagements: solution design, modeling approach, validation strategy, and delivery quality
• Lead and mentor a team of data scientists - code reviews, methodology reviews, career development, and raising the bar on what 'done' means
• Stay hands-on: prototype approaches, unblock the team on hard modeling problems, and contribute production-grade Python where it matters most
• Translate client business problems into scoped, estimable data science workstreams, and push back when the problem doesn't need a model
• Set and enforce engineering standards for the team: reproducibility, experiment tracking, testing, and documentation
• Guide platform decisions and delivery across cloud/data ecosystems - Microsoft Fabric, Palantir Foundry, Databricks, Snowflake, and native Azure/AWS/GCP services
• Work with AI Architects, data engineers, and client stakeholders to align technical decisions with business outcomes and timelines
• Represent the team in front of clients: present results, defend methodology, and manage technical expectations

Skills

Python

Leadership

Data science modeling

Experimentation

Communication

Tools

Microsoft Fabric

Palantir Foundry

Databricks

Snowflake

Cloud services

Job description

Sii Poland is seeking a technical lead to own end-to-end data science projects, framing problems with clients and signing off on modeling approaches. You will mentor a team, review work, and ensure production-grade Python delivery across platforms like Microsoft Fabric, Palantir Foundry, and Databricks.

You will stay hands-on while guiding standards, experimentation, and engineering practices. Fluent English and Polish are required, and you must reside in Poland.