Orhan is available for hire
Hire OrhanOrhan Balotu
Verified Expert in Engineering
Artificial Intelligence (AI) Developer
Istanbul, Turkey
Toptal member since December 28, 2021
Bio
Orhan is a data scientist with a solid mathematical background. Over the last four years, he has worked in global enterprises and small startups. Meanwhile, he managed to practice his theoretical knowledge in various business problems. Orhan's primary focus areas are data-driven decision-making, statistical modeling, and optimization.
Portfolio
dotQIT GmbH
Data Build Tool (dbt), Snowflake, Python, Docker, Apache Airflow...
R2Net, Inc.
Python, SQL, NumPy, Pandas, Apache Airflow, APIs, GraphQL, Tableau...
General Electric Power
Amazon Web Services (AWS), Python 3, GitHub, SQL, Keras, Scikit-learn...
Experience
- Data Science - 8 years
- Artificial Intelligence (AI) - 8 years
- Python - 8 years
- Deep Learning - 6 years
- NumPy - 6 years
- SQL - 5 years
- Amazon Web Services (AWS) - 3 years
- C++ - 2 years
Preferred Environment
Python, Jupyter, Amazon Web Services (AWS), Visual Studio Code (VS Code)
The most amazing...
...project I've developed is the calibration of air pollution sensors with the help of machine learning.
Work Experience
Data Tech Lead
2024 - 2026
dotQIT GmbH
- Architected and managed end-to-end data systems and AI-driven architectures leveraging a modern stack centered on Python, dbt, PostgreSQL, and Snowflake.
- Integrated machine learning and deep learning models to automate decision-making and deployed AI agents to streamline complex data reasoning and workflow optimizations.
- Orchestrated these sophisticated workloads within Kubernetes clusters using Airflow, ensuring the seamless delivery and high availability of data products within an Azure environment.
Technologies: Data Build Tool (dbt), Snowflake, Python, Docker, Apache Airflow, Amazon S3 (AWS S3)
Senior Data Engineer
2022 - 2025
R2Net, Inc.
- Utilized AWS cloud technologies and Python to design and maintain efficient data pipelines for a prominent company in the diamond industry.
- Sourced data from multiple APIs and databases, performed data cleaning and transformation, and scheduled jobs through Airflow to deliver accurate business intelligence to the team.
- Utilized my proficiency in AWS services such as S3, Redshift, Glue, and Lambda to create efficient, scalable, and fault-tolerant data processing pipelines.
- Built demand forecasting models from scratch to support sales and inventory planning within the eCommerce domain.
- Delivered forecasting pipelines for short-term, high-impact sales periods.
- Applied time-series modeling and machine learning techniques to improve forecast accuracy and support data-driven decision making.
- Used linear regression and log-log models to build price elasticity and demand forecasts for high-value diamonds, quantifying how price changes impacted sales volume across different markets.
Technologies: Python, SQL, NumPy, Pandas, Apache Airflow, APIs, GraphQL, Tableau, Microsoft Excel, ETL, Linux, Data Build Tool (dbt), Data Pipelines, PostgreSQL, FastAPI, Snowflake, Docker, AWS Lambda, Amazon S3 (AWS S3), Amazon Redshift
Senior Data Scientist
2021 - 2022
General Electric Power
- Developed machine learning (ML) models to help with financial decision-making.
- Built end-to-end cloud solutions using AWS, like SageMaker, Glue, and more.
- Created a health monitoring system that tracks model performance metrics and data integrity on AWS.
- Conducted meetings with stakeholders to be in line with their business requirements.
- Took part in technical development initiatives, researched up-to-date methods, and introduced them to colleagues.
- Designed statistically-driven financial models for global decision-making, using regression analysis and significance testing to provide confidence intervals for revenue estimations, moving beyond point-estimates to better quantify financial risk.
Technologies: Amazon Web Services (AWS), Python 3, GitHub, SQL, Keras, Scikit-learn, Machine Learning, Data Science, Modeling, Models, Communication, Version Control Systems, Data Analytics, Data Analysis, Data Engineering, Predictive Modeling, Statistical Modeling, Real-time Data, Predictive Analytics, Statistics, APIs, MySQL, AWS Lambda
Artificial Intelligence Software Engineer
2019 - 2021
Baykar Defence
- Took part in developing projects in many different fields to improve the capabilities of unmanned aerial vehicles (UAVs).
- Developed an anomaly detection algorithm in sensors that uses classical time series models and cutting-edge machine learning algorithms.
- Built data-driven physical statistical modeling for complex physical systems. Implemented it to the embedded software.
- Developed smart algorithms to improve the environmental awareness of UAVs.
- Implemented risk evasion algorithms that can calculate the most appropriate path for UAVs.
Technologies: Python, C++, Scikit-learn, NumPy, Pandas, Keras, TensorFlow, PyTorch, Machine Learning, Data Science, Modeling, Models, Communication, Version Control Systems, Data Analysis, Data Engineering, Predictive Modeling, Statistical Modeling, Statistical Analysis, Real-time Data, Predictive Analytics, Statistics, APIs, MySQL
Data Scientist
2017 - 2018
Hawa Dawa
- Processed efficiently high-frequency sensor data on the cloud.
- Calibrated air pollution sensors with machine learning algorithms. Decreased the margin of error significantly.
- Coordinated with the embedded software team for the production phase.
- Created a prediction model from scratch to predict calibration drifts on air pollution detector products, using high-frequency sensor data (CO2, temperature, air particles).
Technologies: Python, Jupyter, Data Science, Scikit-learn, TensorFlow, Machine Learning, Models, Communication, Version Control Systems, Data Analytics, Data Analysis, Data Engineering, Predictive Modeling, Statistical Modeling, Real-time Data, Predictive Analytics, Statistics, APIs, MySQL
Business Analyst
2017 - 2017
Allianz
- Owned the gathering of insights from HR data of more than 70 countries.
- Created efficient KPI reports with Excel VBA that were previously being created manually.
- Reported statistical findings of various estimation methods using R.
Technologies: R, Python, SQL, Excel VBA, Excel 365, Communication, Version Control Systems, Data Analytics, Data Analysis, Predictive Modeling, Statistical Modeling, Statistical Analysis, Statistics
R&D Engineer
2016 - 2016
Car2Go
- Processed and stored real-time data from the API efficiently.
- Created an integer optimization model to minimize the cost of electric vehicles' charging cycle and distribution around the city. Implemented the optimization model in Gurobi, which ran on parallel servers.
- Built an end-to-end system that runs and produces real-time outputs.
Technologies: Linux, Python, Mixed-integer Linear Programming, Data Analysis, Statistics
Online Mathematics Tutor
2015 - 2016
Video Tutor GmbH
- Prepared educational content according to the curriculum for high schools with international certificates.
- Conducted online applied sessions with students in need.
- Built tutorial videos with animations using Microsoft PowerPoint.
Technologies: Microsoft PowerPoint, Mathematics
Teaching Assistant
2015 - 2015
Ozyegin University
- Acted as an assistant professor in statistics and probability courses.
- Created and evaluated exam and homework questions.
- Guided undergraduate students in their end-of-term projects.
- Conducted applied sessions of courses. Introduced numerical statistical methods using MATLAB and R.
Technologies: MATLAB, R
Analyst Intern
2011 - 2011
Turkish Statistical Institute
- Helped the statistics team make sense of the census data.
- Pre-processed data using R and applied statistical approaches with Tableau.
- Created analysis and reporting of the statistical findings.
Technologies: SPSS, Tableau
Experience
Portfolio Optimization Using Neural Networks
This project aims to build a prediction-based portfolio optimization model to capture investment opportunities and I used neural network predictors to predict stocks' returns and derived a risk measure.
Risk Control in Construction Projects with Bayesian Networks
This project deals with an approach to provide better information to derive relevant and effective risk measures for specific risks in construction projects and I built a robust system by adding expert knowledge to the Bayesian network.
Education
2015 - 2018
Master's Degree in Mathematics in Operations Research
Technical University of Munich - Munich, Germany
2009 - 2014
Bachelor's Degree in Mathematics
Istanbul University - Istanbul, Turkey
Certifications
JANUARY 2017 - PRESENT
Eurex Exchange Trader Certificate
Eurex Exchange
Skills
Libraries/APIs
Scikit-learn, NumPy, Pandas, Keras, TensorFlow, PyTorch
Tools
Jupyter, Apache Airflow, GitHub, Microsoft PowerPoint, MATLAB, SPSS, Tableau, Microsoft Excel
Languages
Python, Python 3, SQL, Snowflake, Excel VBA, R, C++, GraphQL
Platforms
Amazon Web Services (AWS), AWS Lambda, Docker, Visual Studio Code (VS Code), Linux
Storage
Data Pipelines, Amazon S3 (AWS S3), MongoDB, MySQL, PostgreSQL
Paradigms
ETL
Other
Data Science, Data Visualization, Artificial Intelligence (AI), Deep Learning, Machine Learning, Modeling, Models, Communication, Version Control Systems, Google Colaboratory (Colab), Data Analytics, Data Analysis, Predictive Modeling, Statistical Modeling, Statistical Analysis, Real-time Data, Predictive Analytics, Statistics, APIs, Data Build Tool (dbt), Time Series Analysis, Amazon Redshift, Data Engineering, Risk Analysis, FastAPI, Forecasting, Demand Forecasting, Time Series Forecasting, Mathematics, Excel 365, Mixed-integer Linear Programming, Trading, Options Trading, Forex Trading
Collaboration That Works
How to Work with Toptal
Toptal matches you directly with global industry experts from our network in hours—not weeks or months.
1
Share your needs
Discuss your requirements and refine your scope in a call with a Toptal domain expert.
2
Choose your talent
Get a short list of expertly matched talent within 24 hours to review, interview, and choose from.
3
Start your risk-free talent trial
Work with your chosen talent on a trial basis for up to two weeks. Pay only if you decide to hire them.
Top talent is in high demand.
Start hiring