Data Scientist with ML (f/m/x)

Sii Sp. z o.o.; Łódź; On-site; PLN 150,000 - 210,000; Full time

Benefits offered by this job

Private healthcare

Remote work

Growth opportunities

Job summary

W Sii Sp. z o.o. w Łodzi poszukujemy Data Scientist z doświadczeniem w ML, który zbuduje i utrzyma modele predykcyjne, wpływające na strategie marketingowe oraz wyniki biznesowe.

Dołączysz do nowo tworzanego zespołu analitycznego w globalnej firmie działającej w różnych branżach. Wymagane co najmniej 5 lat doświadczenia w Data Science, silna znajomość SQL oraz Python (Pandas, NumPy, scikit-learn, statsmodels).

Qualifications

• Minimum 5 lat doświadczenia jako Data Scientist.
• Silna znajomość SQL — tworzenie złożonych zapytań i przygotowanie danych do modelowania.
• Znajomość Pythona (Pandas, NumPy, scikit-learn, statsmodels) – analiza danych, modelowanie i walidacja wyników.
• Doświadczenie w pracy z dużymi zestawami danych i procesami ETL.
• Umiejętność pracy z danymi biznesowymi i interpretacji analitycznych wyników.
• Dbałość o jakość kodu i powtarzalność analiz.
• Umiejętność komunikowania się po angielsku w środowisku międzynarodowym.

Responsibilities

• Budowanie i optymalizacja modeli predykcyjnych (np. churn, propensity, segmentacja, CLV, rekomendacje).
• Analiza danych konsumenckich i marketingowych z różnych źródeł.
• Modelowanie i optymalizacja podróży klienta za pomocą AI/ML.
• Współpraca z zespołami marketingu i produktu w definiowaniu priorytetów analitycznych.
• Tłumaczenie skomplikowanych wyników analitycznych na jasne rekomendacje biznesowe.
• Dostarczanie analiz wraz z praktycznymi wskazówkami dla zespołów biznesowych.
• Przygotowywanie prezentacji, raportów i wizualizacji dla nietechnicznych interesariuszy.
• Śledzenie wydajności modeli i mierzenie wpływu na KPI marketingowych i P&L.
• Identyfikowanie nowych możliwości rozwoju opartego na danych i promowanie decyzji opartych na danych.

Skills

SQL

Python

ETL

Machine Learning

Predictive Models

Tools

Pandas

NumPy

Scikit-learn

Statsmodels

Job description

Data Scientist with ML (f/m/x)

Miejsce pracy: Łódź

Technologies we use

Expected

• SQL
• Python
• ETL
• Machine Learning
• Predictive Models

Optional

• Pandas
• NumPy
• Scikit-learn
• Statsmodels

About the project

We’re looking for an experienced Data Scientist skilled in building predictive models. You will join a newly formed analytics team inside a leading global company in the tobacco industry, shaping how data drives consumer strategy and marketing performance. Your work will focus on predictive modeling, consumer insights and translating analytics into actionable business decisions. If you want your models to truly ‘move the needle’, this role is for you.

Sii ensures that all employment-related decisions are made solely on the basis of qualifications, competencies, and performance. We are committed to equal treatment of all individuals, regardless of any protected characteristics, and promote a diverse and inclusive work environment.

Your responsibilities

• Build and optimize predictive models (e.g., churn, propensity, segmentation, CLV, recommendations)
• Analyze consumer and marketing data across multiple sources
• Model and optimize customer journeys using AI/ML techniques
• Collaborate with marketing and product teams to define analytical priorities
• Translate complex analytical findings into clear business recommendations
• Deliver analytical outputs together with actionable usage guidance for business teams
• Prepare high-quality presentations, reports and data visualizations for non-technical stakeholders
• Track model performance and measure business impact on marketing KPIs and P&L
• Identify new opportunities for data-driven growth and champion data-based decision-making across the organization

Our requirements

• Minimum 5 years of experience as a Data Scientist
• Strong proficiency in SQL – ability to write complex queries, join large datasets, and prepare data for modeling
• Proficiency in Python (libraries such as pandas, numpy, scikit-learn, statsmodels, or similar) – focus on data analysis, modeling, and result validation
• Experience working with large datasets and ETL processes
• Ability to work with business data and interpret analytical results
• Attention to code quality and reproducibility of analyses
• Ability to communicate effectively in English in an international environment

Optional

• Expertise in the marketing and consumer analytics domain
• Good understanding of segmentation models (clustering, scoring, customer profiling) and predictive models (propensity, churn, LTV)
• Basic knowledge of model validation and performance metrics (AUC, lift, confusion matrix)

What we offer

• Great Place to Work since 2015 - it’s thanks to feedback from our workers that we get this special title and constantly implement new ideas
• Employment stability - revenue of PLN 2.1BN, no debts, since 2006 on the market
• We share the profit with Workers - over PLN 76M has already been allocated for this aim since 2022
• Attractive benefits package - private healthcare, benefits cafeteria platform, car discounts and more
• Comfortable workplace - class A offices or remote work
• Dozens of fascinating projects for prestigious brands from all over the world – you can change them thanks to Job Changer application
• PLN 1 000 000 per year for your ideas - with this amount, we support the passions and voluntary actions of our workers
• Investment in your growth – meetups, webinars, training platform and technology blog – you choose
• Fantastic atmosphere created by all Sii Power People

Sii Sp. z o.o.

Sii is the leading technology consulting, digital transformation, engineering, and business services vendor in Poland. We already employ more than 7 300 professionals and implement projects in a variety of industries for clients from many countries around the world. The Great Place to Work title, won 10 times in a row, proves that at Sii, we create a friendly work environment.

Sii ensures that all employment-related decisions are made solely on the basis of qualifications and competencies. We are committed to equal treatment of all individuals, regardless of any protected characteristics, and promoting a diverse and inclusive work environment.