Technical Lead, Data Science — Hands-On & Mentoring

Sii Poland; Piła; On-site; PLN 180,000 - 300,000; Full time

Benefits offered by this job

Great Place to Work

Centre of internal trainings

Profit sharing

Open management team

Many experts you can learn from

Comfortable and well-equipped offices

MySii app

Medical care

Job summary

Sii Poland is seeking a technical lead to steer end-to-end data science projects. You will own problem framing, modeling decisions, and delivery quality while mentoring a team of data scientists.

You’ll stay hands-on with Python, review model choices, and drive standards across platforms like Microsoft Fabric, Palantir Foundry, and Databricks. Fluent in English and Polish, you’ll work in Poland with clients and internal stakeholders.

Qualifications

• 6+ years in data science with models shipped to production.
• Hands-on Python across the standard data stack (pandas, NumPy, scikit-learn, XGBoost).
• Strong statistical and ML foundations and experimental design.
• Familiarity with at least one cloud/data platform and its data science components.
• Experience leading delivery in client-facing or consulting contexts.
• Strong communication skills to defend methodology to technical and business audiences.
• Fluent in English and Polish; willing to reside in Poland.

Responsibilities

• Own the technical direction of data science engagements, including design, modeling approach, validation, and delivery quality.
• Lead and mentor a team of data scientists, including code reviews and career development.
• Stay hands-on by prototyping approaches and contributing production-grade Python where it matters.
• Translate client problems into scoped, estimable data science workstreams and push back when a model isn’t needed.
• Set and enforce engineering standards: reproducibility, experiment tracking, testing, and documentation.
• Guide platform decisions and delivery across cloud/data ecosystems (Fabric, Foundry, Databricks, Snowflake, AWS/GCP/Azure).
• Collaborate with AI architects and clients to align decisions with business timelines and outcomes.
• Represent the team to clients, presenting results and defending methodologies.

Skills

Team leadership

Python (data science stack)

Statistics & ML fundamentals

English communication

Polish language

Client-facing communication

Tools

Azure

SageMaker

Vertex AI

Databricks

Snowflake

Palantir Foundry

Microsoft Fabric

Job description

Sii Poland is seeking a technical lead to steer end-to-end data science projects. You will own problem framing, modeling decisions, and delivery quality while mentoring a team of data scientists.

You’ll stay hands-on with Python, review model choices, and drive standards across platforms like Microsoft Fabric, Palantir Foundry, and Databricks. Fluent in English and Polish, you’ll work in Poland with clients and internal stakeholders.