About the job
Please submit your CV in English and specify your English proficiency level.
toloka-ai, in partnership with Mindrift, offers project-based contract opportunities for experienced data science engineers. Projects focus on testing, evaluating, and improving AI systems for leading technology clients. This is not a permanent employment role but rather contract work based on individual assignments.
Role overview
Freelance Data Science Engineers (Python & SQL) work on a variety of projects, each with unique analytical and computational challenges. Assignments involve designing original data science problems that reflect real-world business scenarios in sectors such as telecom, finance, government, e-commerce, and healthcare.
- Create computational problems that require advanced analytical workflows and cannot be solved manually in a short time.
- Design tasks solvable in Python, using libraries like Pandas, Numpy, Scipy, scikit-learn, Statsmodels, Matplotlib, and Seaborn.
- Develop scenarios involving data processing, statistical analysis, feature engineering, predictive modeling, and extracting business insights.
- Ensure each problem is deterministic and reproducible, using fixed seeds when randomness is necessary.
- Base challenges on real business needs, such as customer analytics, risk assessment, fraud detection, forecasting, optimization, and operational efficiency.
- Cover the full data science workflow: from data ingestion and cleaning to modeling, validation, and deployment considerations.
- Include big data scenarios that require scalable computational solutions.
- Validate solutions in Python with established libraries and statistical methods.
- Document each problem clearly, providing realistic business context and verified answers.
Requirements
- Minimum 5 years of hands-on data science experience with measurable business outcomes.
- Portfolio of completed projects or publications showing practical problem-solving skills.
- Advanced Python programming for data science, including experience with pandas, numpy, scipy, scikit-learn, and statsmodels.
- Strong knowledge of statistical analysis and machine learning algorithms.
- Proficient SQL skills and experience with database operations for analysis.
- Familiarity with Generative AI tools and techniques such as LLMs, RAG, prompt engineering, and vector databases.
- Understanding of MLOps and model deployment workflows.
- Knowledge of frameworks like TensorFlow, PyTorch, or LangChain.
- Excellent written English at C1 level or above.
Application process
- Submit your CV and indicate your English proficiency level.
- Complete the qualification steps.
- If selected, join a project.
- Work on assigned tasks.
- Receive compensation for completed work.
Location: Remote , Sweden

