Senior Data Scientist (AI)

Location: Sofia, Bulgaria; hybrid; flexible working hours and home office available.

Company

hirify.global is a global data and technology company serving markets including financial services, healthcare, automotive, agribusiness, and insurance.

What you will do

• Analyze, process, and document large datasets using analytical, machine learning, and data mining techniques.
• Develop and maintain data structures, storage schemes, processing tools, and analytical pipelines.
• Monitor model performance and stability, including validation, back-testing, and performance reporting.
• Investigate data and model issues, identify root causes, and implement corrective actions or model updates.
• Maintain documentation, version control, audit trails, and data quality practices for governance and compliance.
• Assess model outputs, conduct ROI and benefit analyses, present findings, and develop best practices and business assumptions.

Requirements

• Strong understanding of probability, statistical inference, optimization algorithms, linear algebra, and calculus.
• Understanding of regression analysis, machine learning, AI, deep learning, and other advanced modeling approaches.
• Strong understanding of model cross-validation and methods for penalizing unnecessary complexity, including regularization, Bayesian shrinkage, and in-sample versus out-of-sample evaluation.
• Fluency with statistical significance tests and Monte Carlo simulation.
• Ability to write near-production-level code in at least one general-purpose programming language, such as Python or C++.
• Understanding of technologies for processing large datasets, including Apache technologies such as Hadoop and Spark, modern databases such as graph and time-series databases, and natural language processing tools for parsing unstructured data.

Culture & Benefits

• Career development pathways, learning and development programs, online educational training, learning materials, and books.
• Friendly work environment, recognized team spirit, and recreation time.
• Social benefits including life insurance, food vouchers, additional health insurance, monthly flex allowance, internet coverage, corporate discounts, family allowances, a Multisport card, Sharesave plan, and employee assistance program.
• 25 days of paid vacation, one additional birthday day off, and three paid days for social responsibility events.
• Flexible working hours and home office options.
• Inclusive, equal-opportunity workplace with accommodation available for disabilities or special needs.