Data Scientist – Python & Cloud Data Platforms (f/m/x)

Sii operates in multiple Polish cities including Warszawa, Wrocław, Kraków, Gdańsk, Poznań, Katowice, Białystok, Bydgoszcz, Lublin, and Łódź. The company focuses on enterprise AI projects that include generative AI, agentic AI, and AI platforms across various domains such as legal document compliance and autonomous driving.

• Minimum 4 years of experience in data science or applied analytics with successful deployment beyond prototypes
• Strong proficiency in Python and the standard data stack (pandas, NumPy, scikit-learn)
• Solid statistical knowledge including hypothesis testing, regression, and experimental design
• Experience with at least one cloud or data platform and its data science tools (e.g., Microsoft Fabric, Azure Machine Learning, AWS SageMaker, GCP Vertex AI, Snowflake, Databricks, Palantir Foundry)
• Ability to clearly communicate analytical results to business stakeholders
• Experience working autonomously and collaborating with data engineers, architects, and product teams
• Fluent in both English and Polish (C1 level)
• Residency in Poland required

Nice to have:

• Production experience with Microsoft Fabric or certification in Palantir Foundry
• Experience with time series forecasting, NLP, recommender systems, or LLM workflows
• Familiarity with MLOps practices including MLflow, experiment tracking, and CI/CD for ML
• Experience with Power BI, other BI tools, and distributed processing with Spark/PySpark

• Translate business problems into analytical solutions by defining hypotheses, selecting metrics, and modeling approaches
• Explore, clean, and prepare data using Python (pandas, NumPy), handling structured and semi-structured sources
• Build, validate, and tune machine learning models for classification, regression, forecasting, segmentation, and recommendation using scikit-learn, XGBoost, and statsmodels
• Design and analyze experiments including A/B tests, statistical hypothesis testing, and causal analysis
• Work hands-on with enterprise data platforms such as Microsoft Fabric and Palantir Foundry for notebooks, lakehouses, pipelines, and operational workflows
• Communicate findings through visualizations, dashboards, and narratives tailored to diverse audiences
• Collaborate with data engineers on data quality and availability, and with ML/AI engineers to deploy models
• Monitor deployed models for drift and degradation and manage the retraining and improvement cycle

Residing in Poland is required for this position.