Data Scientist (Mid)

At neXa, we’re not just building digital solutions — we’re helping businesses grow smarter. We work with forward-thinking clients across industries to design, build, and implement technology that makes a real difference. From intelligent automation to custom applications, our projects are as diverse as our team.

We’re now looking for a Mid Data Scientist to join a high-energy team focused on building advanced data-driven solutions and developing machine learning models. In this role, you will work on designing algorithms, improving data quality, and transforming complex datasets into actionable insights. You will have the opportunity to apply modern data science techniques, experiment with new approaches, and contribute to solutions that support smarter decision-making.

The role is based in Poland (Warsaw/Poznań) – remote work + visiting one of the offices once in 2 months.
B2B contract (long-term cooperation)

Responsibilities:

• Design, develop, and optimize machine learning models for data-driven solutions

• Build and improve algorithms for data mapping, classification, and information quality enhancement

• Analyze complex datasets to identify patterns, trends, and opportunities for improvement

• Translate business challenges into data science solutions and actionable recommendations

• Conduct statistical analyses, experiments, and causal inference studies

• Apply advanced modeling techniques, including gradient boosting, Bayesian methods, optimization, deep learning, and generative AI approaches

• Work with large-scale datasets using modern data processing tools

• Ensure high quality, scalability, and reusability of developed solutions and code

• Collaborate with technical and business stakeholders to deliver impactful data products

• Communicate analytical findings and recommendations through effective data visualization and presentations

Requirements:

• Proven experience as a Data Scientist or in a similar data-focused role, with ownership of delivered solutions

• Ability to independently identify business problems and transform data into practical insights

• Strong statistical background enabling advanced experimentation and causal analysis

• Practical experience with machine learning techniques, including:
  – Gradient boosting
  – Bayesian methods
  – Causal inference
  – Optimization algorithms
  – Deep learning
  – Generative AI (LLM, Agentic AI)

• Experience working with large datasets using Python, BigQuery, and Spark

• Strong programming practices with focus on code quality, maintainability, and reusability

• Experience with version control systems

• Good knowledge of data analysis and visualization techniques

• Good command of English (B2+ level or higher) and Polish (C1+)

Nice to have:

• Experience building classification systems

• Hands-on experience with Large Language Models (LLM)

• Knowledge of Data Studio or similar data visualization tools

• Experience working with AI-driven recommendation systems

• Experience in developing automated data quality solutions