Data Scientist

About us:

As a leading telecommunications infrastructure provider in the region, CETIN drives digital transformation with a strong presence across Bulgaria, Hungary, Serbia, and Slovakia. Through our subsidiaries, we deliver advanced technology solutions that empower connectivity and enable innovation.
CETIN owns and operates some of the largest telecommunications networks in Bulgaria and Serbia, committed to delivering high-quality, cutting-edge infrastructure that meets and exceeds our customers’ technological needs. Our focus is on developing and deploying world-class telecommunications infrastructure to tackle the dynamic demands of today’s market.
At CETIN, we bring together highly skilled and motivated experts dedicated to excellence. 

Join us to be part of a team shaping the future of telecommunications!

Role Overview:

As a Data Scientist, you will be at the forefront of using advanced analytics, machine learning, and statistical modeling to extract insights and build predictive systems that enhance the performance, reliability, and intelligence of telecom networks. Working across Radio, Core, Transport, and IT infrastructure domains, you will find patterns, predict behaviors, and support the automation of decision-making processes through data.

You’ll collaborate with Data Engineers, Analysts, and Network/IT teams to build scalable ML workflows, validate hypotheses, and translate domain knowledge into data-driven models. This role combines a strong mathematical background with firsthand coding skills and a passion for experimentation.

Key Responsibilities:

• Explore and model complex datasets to identify trends, correlations, and patterns in network and operational data
• Design and implement statistical and machine learning models for predictive maintenance, anomaly detection, fault classification, and customer experience analytics
• Collaborate with engineers and domain experts to define use cases and translate them into end-to-end data science solutions
• Build and validate features from structured, unstructured, and time series data
• Use Python and open-source libraries to perform EDA, modeling, evaluation, and visualization
• Contribute to model deployment and monitoring within production-grade pipelines (in cooperation with Data Engineers)
• Communicate findings through notebooks, reports, visualizations, and stakeholder briefings
• Support model lifecycle management, from experimentation to retraining and maintenance

Required Technical Skills:

• University degree, and/or strong ability in Python for data science (pandas, NumPy, scikit-learn, statsmodels, Gradient boosting algorithms, PyTorch/TensorFlow is a plus)
• Solid understanding of statistics, probability, time series analysis, and ML algorithms (classification, regression, clustering, anomaly detection)
• Experience with SQL for feature extraction and data preparation from relational databases
• Hands-on experience with Jupyter Notebooks for prototyping and experimentation
• Exposure to working with large-scale datasets, especially in telecom, log data, or sensor networks
• Familiarity with visualization tools like Power BI, Superset, matplotlib, seaborn, or plotly
• Basic understanding of MLOps principles and model deployment (e.g., using Airflow, Docker, or REST APIs)
• Familiarity with GIS data and geospatial analysis is a plus

Soft Skills & Expectations:

• Analytical mindset with a scientific approach to experimentation
• Ability to understand domain problems and convert them into data science projects
• Comfortable communicating complex concepts to both technical and non-technical stakeholders
• Self-organized, curious, and eager to explore modern technologies and techniques
• Fluent in English (written and verbal)
• Team player with a collaborative and open attitude

What we offer:
•    Open working space and flexible working hours

•    Training and development programs
•    25 days paid holiday leave per annum 
•    Laptop, mobile phone and tariff package in line with company policy
•    Private health insurance
•    Recreation or health program 
•    Participation in annual bonus system
•    Competitive terms and conditions
 
Only short-listed candidates will be contacted