You're seeing this page as if you were . The main menu is still yours, though. Exit from immersion
Zornitsa TonozlievaZT

Zornitsa Tonozlieva

Senior ML Engineer

€500/day
Sofia, BG
3-7 years

Average response time: 1 hour

About Zornitsa

Senior ML engineer with 6 years building production machine learning systems across financial services, healthcare, and energy. I take projects end to end — from framing the problem with stakeholders to deploying and maintaining models that actually run in production.
My core strengths span three areas: forecasting (currently building electricity price and grid-imbalance models hitting 92%+ directional accuracy for an energy-trading platform), LLM and RAG systems (I've built LLM-powered tools for regulatory compliance and document automation), and the MLOps to put both into production (AWS/SageMaker, Docker, robust data pipelines). I work comfortably across the full stack of a data problem - Python, SQL, PySpark, large-scale datasets.
I value clear communication and genuine ownership. Available for remote engagements across European time zones.
  • English

    Native or bilingual

  • Bulgarian

    Native or bilingual

Remote only
Primarily works remotely

Experience

  • Adex Energy
    Data Scientist
    ENERGY AND UTILITIES
    October 2025 - Today (9 months)
    Sofia, SF, Bulgaria
    • • Developing ml models for electricity price forecasting in the Bulgarian energy market
    • • Building system imbalance prediction models achieving 92%+ directional accuracy with confidence-based trade selection strategies
    • • Forecasting energy consumption and production patterns to support grid balancing operations and costs
    • • Working with time-series data pipelines using InfluxDB
    Machine learning Python
  • Experian
    Machine Learning Engineer
    August 2022 - October 2025 (3 years and 2 months)
    Sofia, Bulgaria
    Implemented predictive models utilizing Pandas, NumPy, and scikit-learn to identify market trends and opportunities. Developed LLM-powered documentation tool for regulatory model compliance, automating technical documentation generation. Leveraged AWS technologies (EMR clusters, S3, Athena, SageMaker), Hadoop, and Spark/PySpark to process and analyze large-scale financial datasets Authored complex SQL queries handling datasets exceeding 1 million records to generate automated reports that improved stakeholder visibility into key performance indicators. Architected back-end systems for an enterprise analytics platform enabling clients to leverage machine learning models for financial decision-making. Built robust data validation and processing pipelines using Pydantic, Pandera, and Jinja for complex code generation and templating.
    LLM RAG Python Pandas Machine learning
  • Lanterne
    Data Engineer
    January 2022 - August 2022 (7 months)
    London, UK
    Engineered data solutions in a fast-paced startup using Python (Pandas, NumPy) and AWS services (Lambda, CloudWatch, S3, DynamoDB). Developed backend systems, contributed to critical business decisions, authored technical design documents, and identified product enhancement opportunities through data-driven insights.
    Python Data science

Recommendations

Be the first to recommend Zornitsa

Help this freelancer shine by sharing your experience working together.

These freelancer profiles also match your criteria

AgathaA

Agatha Frydrych

Backend Java Software Engineer

4.7

(3)

2

BaptisteB

Baptiste Duhen

Fullstack developer

4.6

(4)

5

AmedA

Amed Hamou

Senior Lead Developer

4

(2)

7

AudreyA

Audrey Champion

Web developer

4.3

(3)

4

Education

  • BSc Computer Science
    University of Birmingham
    2017
    BSc
  • deeplearning.ai certified: Neural Networks and Deep Learning Structuring Machine Learning Projects Improving Deep Neural Networks
    deeplearning.ai certified: Neural Networks and Deep Learning Structuring Machine Learning Projects Improving Deep Neural Networks

Categories