Data Science Tech Lead - Hands-on & Mentorship

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

Benefits offered by this job

Great Place to Work

Solid financial situation

Contracts with big brands

Internal trainings

Mentor network

Job summary

Sii Poland is seeking a technical lead in data science to steer end-to-end projects. You will own model framing, solution design, and delivery while mentoring the team and maintaining hands-on coding in Python where it matters most.

You will collaborate with AI architects and data engineers across cloud platforms, ensuring robust, scalable solutions. Fluency in English and Polish, plus residing in Poland, are required for this on-site leadership role.

Qualifications

• 6+ years in data science with production models shipped.
• Minimum 2 years leading or mentoring other data scientists.
• Deep Python skills across pandas, NumPy, scikit-learn, XGBoost.
• Experience with at least one cloud/data platform (Azure, AWS, GCP, Snowflake, Databricks, Palantir).
• Strong design, evaluation, and delivery judgment for client projects.
• Excellent communication and ability to defend methodology to both technical and non-technical audiences.

Responsibilities

• Own the technical direction of data science engagements from framing to delivery.
• Lead and mentor a team of data scientists, conducting reviews and setting standards.
• Stay hands-on with prototype work and production-grade Python when needed.
• Translate client problems into scoped, estimable data science workstreams.
• Set engineering standards for reproducibility, experiments, testing, and docs.
• Guide platform decisions across cloud/data ecosystems (Fabric, Foundry, Databricks, Snowflake, Azure/AWS/GCP).
• Collaborate with AI Architects and client stakeholders to align decisions with business goals.
• Represent the team in client meetings, presenting results and managing expectations.

Skills

Data science leadership

Python

Statistical ML

Cloud platforms

Client-facing

Communication

English

Polish

Poland residency

Job description

Sii Poland is seeking a technical lead in data science to steer end-to-end projects. You will own model framing, solution design, and delivery while mentoring the team and maintaining hands-on coding in Python where it matters most.

You will collaborate with AI architects and data engineers across cloud platforms, ensuring robust, scalable solutions. Fluency in English and Polish, plus residing in Poland, are required for this on-site leadership role.