Senior Data Scientist — AI and Enterprise Platform Expert

Sii Poland; Toruń; On-site; PLN 180,000 - 240,000; Full time

Benefits offered by this job

Great Place to Work

Solid financial situation

Contracts with big brands

Centre of internal trainings

Many experts you can learn from

Open management team

Profit sharing

Sii app

Medical care

Job summary

Sii Poland is seeking data scientists who turn ambiguous business questions into models and analyses that get used. You will frame problems, wrangle data, build and validate models, and explain what numbers mean to people who don’t speak Python.

You'll work with the classic Python stack (pandas, NumPy, scikit-learn) and modern platforms like Microsoft Fabric and Palantir Foundry, deploying analytics on Azure, AWS, or GCP. This role offers diverse projects and strong growth opportunities.

Qualifications

• 4+ years in data science or applied analytics.
• Strong Python skills across the standard data stack (pandas, NumPy, scikit-learn).
• Solid statistical foundations: hypothesis testing, regression, experimental design.
• Knowledge of at least one cloud/data platform — Azure, AWS, GCP, Snowflake, Databricks, or Palantir.
• Fluent English and Polish; residing in Poland.

Responsibilities

• Translate business problems into analytical solutions: define hypotheses, choose metrics, and select the right modeling approach.
• Explore, clean, and prepare data using Python (pandas, NumPy).
• Build, validate, and tune ML models for classification, regression, forecasting, segmentation, and recommendation using scikit-learn, XGBoost, and statsmodels.
• Design and analyze experiments: A/B tests, hypothesis testing, and causal analysis.
• Work with Microsoft Fabric and Palantir Foundry for notebooks, pipelines, and workflows.
• Communicate findings through clear visualizations and narratives to diverse stakeholders.
• Collaborate with data engineers and ML engineers to move models to production.
• Monitor deployed models for drift and retraining needs.

Job description

Sii Poland is seeking data scientists who turn ambiguous business questions into models and analyses that get used. You will frame problems, wrangle data, build and validate models, and explain what numbers mean to people who don’t speak Python.

You'll work with the classic Python stack (pandas, NumPy, scikit-learn) and modern platforms like Microsoft Fabric and Palantir Foundry, deploying analytics on Azure, AWS, or GCP. This role offers diverse projects and strong growth opportunities.