Dénes is available for hire
Hire DénesDénes Bartha
Verified Expert in Engineering
Machine Learning Developer
Singapore, Singapore
Toptal member since December 7, 2018
Bio
As a PhD student of computer science, Dénes has worked as a researcher in bioinformatics at the University of Tokyo and the National University of Singapore. He has also contributed as a software engineer at Canadian Aviation Engineering (CAE). Dénes greatly enjoys using machine learning (ML) techniques to solve real-world problems and help businesses.
Portfolio
BrixIT Pte. Ltd.
Python, C, C++, MicroPython, Embedded Systems, ESP32, Raspberry Pi, PCB Design...
Dkatalis
TensorFlow, Google Cloud Platform (GCP), BigQuery, Python, AutoML...
Doctor Anywhere
BigQuery, Python, MySQL, Tableau, Google Cloud Platform (GCP)...
Experience
- Python - 12 years
- Machine Learning - 12 years
- C++ - 10 years
- Artificial Intelligence (AI) - 6 years
- TensorFlow - 4 years
- Scikit-learn - 3 years
- BigQuery - 3 years
- Hardware Development - 3 years
Preferred Environment
Jupyter Notebook, PyCharm, Git, Ubuntu, Google Cloud Platform (GCP), Sensor Data
The most amazing...
...tool I've made is a DNA data compression/assembler program called Colorgram that is a Succinct Colored de Bruijn Graph variant.
Work Experience
Founder | CEO | Product Architect
2024 - 2026
BrixIT Pte. Ltd.
- Founded BrixIT Pte. Ltd. in Singapore and led the end-to-end development of DrBartha Toys, a software-enabled coding brick system that teaches programming concepts to children through tactile, screen-free play.
- Designed the complete product architecture for DrBartha Toys, combining smart magnetic coding bricks, custom electronics, embedded firmware, and a companion CodePad device into an executable physical programming system.
- Implemented custom UART and I2C communication protocols to coordinate multiple connected hardware modules and reliably translate physical brick sequences into program behavior.
- Designed and manufactured custom PCBs for the CodePad and coding bricks, covering schematic design, board layout, component selection, prototyping, assembly coordination, and testing.
- Built multiple hardware prototype iterations using custom PCBs, 3D-printed shells, pogo-pin connections, magnetic connectors, RGB LEDs, displays, microcontrollers, and power-management components.
- Managed the hardware manufacturing pipeline across PCB fabrication, PCBA, plastic enclosure development, component sourcing, factory communication, quality control, and assembly planning.
- Programmed and prepared thousands of microcontrollers for production, enabling scalable manufacturing of smart coding bricks with differentiated instruction logic.
- Developed learning activities and early curriculum concepts for children aged approximately 4-12, translating programming concepts such as sequencing, loops, conditionals, variables, and debugging into hands-on physical challenges.
Technologies: Python, C, C++, MicroPython, Embedded Systems, ESP32, Raspberry Pi, PCB Design, Electrical Engineering, Firmware Development, Universal Asynchronous Receiver/Transmitter (UART), I2C, Bluetooth Low Energy (BLE), Hardware Prototyping, Product Development, 3D CAD, Firebase, Google Cloud Platform (GCP), Serverless Architecture, TypeScript, Large Language Models (LLMs), Open-source LLMs, Small Language Models (SLMs), Claude Code
Senior Data Scientist | ML Engineer
2020 - 2024
Dkatalis
- Implemented an ML pipeline for transaction classification in GCP, orchestrated via Dataflow and Kubeflow. Conducted model training and hyperparameter tuning by Vertex AI AutoML and built custom models using Katib with LightGBM, Bert, and TensorFlow.
- Developed a machine learning pipeline to detect recurring transactions based on customer and transaction information. The model populated the "Plan Ahead" feature on the app's front end based on detected recurring transactions.
- Integrated an in-house built TensorFlow Lite YOLO model for automatically detecting IC cards. Added image quality checks to the front end and employed Google Vision Text Recognition for parsing content, applying NLP techniques for result cleansing.
- Participated in creating an API service that shows various insights to the users in the mobile app via Braze, orchestrated with Kafka, using Redis and PostgreSQL.
- Established data quality frameworks for our database in BigQuery, implemented in Python using Great Expectations and orchestrated via Apache Airflow. Implemented a custom SQL unit testing framework.
Technologies: TensorFlow, Google Cloud Platform (GCP), BigQuery, Python, AutoML, Cloud Dataflow, Kubeflow, Kubernetes, BERT, Natural Language Processing (NLP), Language Models, Apache Airflow, Data Build Tool (dbt), Terraform, Scikit-learn, You Only Look Once (YOLO), Dart, Machine Learning, Artificial Intelligence (AI), PyTorch, Pandas, Google Colaboratory (Colab), Convolutional Neural Networks (CNNs), Computer Vision, Deep Learning, Recurrent Neural Networks (RNNs), Large Language Models (LLMs), Machine Learning Operations (MLOps), Fivetran, Generative Artificial Intelligence (GenAI), Data Science, Data Visualization, Data Analysis, Data Scraping, SQL, Data Engineering, Time Series Analysis, Predictive Analytics, Back-end, Databases, PostgreSQL, Google APIs, OAuth 2, REST APIs, LangChain, AI Chatbots, FastAPI, Redis, Puppeteer, Optical Character Recognition (OCR), Retrieval-augmented Generation (RAG), Vector Databases, Data Lakes, ETL, Google Cloud, Flask, Flutter, Agentic AI, Model Tuning, Object Detection, OpenCV, Hugging Face, YOLOv5, YOLOv8, Large Language Model Operations (LLMOps), APIs, Statistical Analysis, Statistics, Statistical Data Analysis, Data Analytics, Mathematical Statistics, Looker Studio, Mixpanel, Looker, Statistical Modeling, Forecasting, JavaScript, Firebase, Prompt Engineering, Recommendation Systems, ChatGPT, Fine-tuning, Llama 3, Open-source LLMs, CI/CD Pipelines, Docker, Full-stack Development, OpenAI API, Minimum Viable Product (MVP), Architecture, Unit Testing, Pytest, DevOps, Serverless Architecture, Banking & Finance, Fintech, Finance, A/B Testing, Google Analytics, Statistical Methods, Google BigQuery, OpenAI, Pattern Recognition, Predictive Modeling, JSON, Analytics, Deep Reinforcement Learning, Reinforcement Learning, AI Prompts, PySpark, Performance, Pricing, Pricing Models, AI Agents, Data Pipelines, Vertex AI, NumPy, Model Evaluation, Model Deployment, Model Monitoring
Senior Data Scientist | ML Engineer
2019 - 2020
Doctor Anywhere
- Helped finance, operations, marketing, BD, and doctors for creating/automating reports in Python and MySQL, sending out daily mails automatically from AWS and GCP Linux virtual machines.
- Automated the integration of a 3rd-party healthcare platform used by our clinics via their API in Python and JavaScript. The platform was missing some CMS functionalities, e.g., setting low stock alerts and calculating cost prices automatically.
- Implemented a pipeline in Python for pulling data from various sources, including multiple MySQL servers, MongoDB, Microsoft SQL Server, and Firebase into BigQuery.
- Created long, flat tables and views in BigQuery using Standard SQL and integrated these with Tableau so that other teams could easily access and analyze the data independently.
- Created an ensemble Random Forest classifier in Python using scikit-learn libraries to predict patient diagnoses based on symptoms, reducing doctors' logging time and filtering unsuitable cases.
- Estimated patients' claim prices using XGBoost in Python.
- Optimized medication delivery routes by analyzing rider data and geolocation data using Standard SQL and Python.
Technologies: BigQuery, Python, MySQL, Tableau, Google Cloud Platform (GCP), Amazon Web Services (AWS), JavaScript, Scikit-learn, XGBoost, Machine Learning, Artificial Intelligence (AI), TensorFlow, PyTorch, Pandas, Google Colaboratory (Colab), Computer Vision, Deep Learning, Large Language Models (LLMs), Machine Learning Operations (MLOps), Microsoft Power BI, Data Science, Data Visualization, Data Analysis, Data Scraping, SQL, Data Engineering, Time Series Analysis, Predictive Analytics, Back-end, Databases, PostgreSQL, Google APIs, OAuth 2, REST APIs, LangChain, AI Chatbots, FastAPI, Redis, Puppeteer, Optical Character Recognition (OCR), Retrieval-augmented Generation (RAG), Data Lakes, ETL, Google Cloud, Flask, Google Maps, Model Tuning, Object Detection, OpenCV, Hugging Face, Large Language Model Operations (LLMOps), APIs, Statistical Analysis, Statistics, Statistical Data Analysis, Data Analytics, Mathematical Statistics, Looker Studio, Mixpanel, Looker, Statistical Modeling, Forecasting, Firebase, Recommendation Systems, Fine-tuning, Open-source LLMs, CI/CD Pipelines, Docker, Full-stack Development, Minimum Viable Product (MVP), Architecture, Unit Testing, Pytest, DevOps, Serverless Architecture, Healthcare, A/B Testing, Google Analytics, Statistical Methods, Google BigQuery, Pattern Recognition, Predictive Modeling, JSON, Analytics, Deep Reinforcement Learning, Reinforcement Learning, AI Prompts, PySpark, Performance, Pricing, Pricing Models, Data Pipelines, Vertex AI, NumPy, Model Evaluation, Model Deployment, Model Monitoring
Python Engineer
2019 - 2019
Resero Analytics, Inc.
- Developed visualizations and analyzed clinical pathology data within a Django framework.
- Built interactive dashboards using Power BI, Matplotlib, Seaborn, and PostgreSQL.
- Streamlined data processing workflows for improved performance and scalability.
Technologies: Python, Django, Pandas, jQuery, Bokeh, Minimum Viable Product (MVP), Architecture, Unit Testing, Pytest, DevOps, A/B Testing, Google Analytics, Statistical Methods, JSON, Analytics, Deep Learning, Performance, Data Pipelines, NumPy, Model Evaluation, Model Deployment, Model Monitoring
Researcher
2018 - 2019
National University of Singapore
- Worked in the bioinformatics laboratory of the Computer Science Department.
- Created design and implementation of concrete bioinformatical algorithms.
- Analyzed data and statistics of human and virus DNA.
- Worked on DNA compression and assembly-related problems.
- Created Colorgram—succinct colored de Bruijn graph.
Technologies: Python, C++, Pandas, Data Visualization, Data Analysis, Databases, Bioinformatics, Statistical Analysis, Statistics, Statistical Data Analysis, SQL, Data Analytics, Mathematical Statistics, Statistical Modeling, Unit Testing, Pytest, Statistical Methods, JSON, Analytics, Performance, Graph Databases, NumPy
Researcher
2016 - 2017
University of Tokyo
- Worked in a bioinformatics laboratory. Created theoretical algorithms related to bioinformatical problems.
- Analyzed mass spectrometry data and implemented and tested various DNA reconstruction algorithms.
- Created and presented statistics and published results in Acta Cybernetica scientific journal.
Technologies: Python, C++, Pandas, Data Visualization, Data Analysis, SQL, Databases, Bioinformatics, Statistical Analysis, Statistics, Statistical Data Analysis, Data Analytics, Mathematical Statistics, Statistical Modeling, Unit Testing, Pytest, Statistical Methods, Pattern Recognition, JSON, Analytics, Performance, Graph Databases, NumPy, Model Evaluation
Software Engineer
2014 - 2017
Canadian Aviation Electronics (CAE)
- Supported the development of the pilot training system by working on both the UI and the back end.
- Maintained the components by analyzing the customers' data and feedback.
- Designed and developed a specific communication system for military aircraft.
- Collaborated (daily) between the Hungarian and Canadian sites.
Technologies: C#, Python, C++, Machine Learning Operations (MLOps), Back-end, Databases, REST APIs, APIs, Statistical Analysis, Statistics, Statistical Data Analysis, SQL, Data Analytics, JavaScript, CI/CD Pipelines, Full-stack Development, Minimum Viable Product (MVP), Architecture, Unit Testing, Pytest, Web Development, DevOps, Pattern Recognition, JSON, Analytics, Performance, Java
Data Scientist
2014 - 2014
Nextent Informatics Co.
- Provided support for the customer data collection process.
- Performed data analysis through advanced machine learning algorithms.
- Supported the creation and design of the mobile application.
Technologies: Android, Python, R, Machine Learning, Artificial Intelligence (AI), Pandas, Deep Learning, Machine Learning Operations (MLOps), Data Science, Data Visualization, Data Analysis, SQL, Predictive Analytics, Back-end, Databases, REST APIs, Data Lakes, Model Tuning, APIs, Statistical Analysis, Statistics, Statistical Data Analysis, Data Analytics, Mathematical Statistics, Statistical Modeling, Forecasting, JavaScript, Recommendation Systems, Fine-tuning, Full-stack Development, Minimum Viable Product (MVP), Architecture, Unit Testing, Pytest, DevOps, Banking & Finance, Fintech, Finance, A/B Testing, Statistical Methods, Pattern Recognition, Predictive Modeling, JSON, Analytics, Performance, Data Pipelines, Java, Model Evaluation, Model Deployment, Model Monitoring
Software Developer
2011 - 2012
Key-Soft plc
- Participated in the development of a billing software.
- Developed and maintained database systems with PL/SQL.
- Developed components of the billing software product.
- Supported the development of an online bookstore in PHP, SQL.
- Worked on this internship program outside the university.
Technologies: PHP, PL/SQL, C++, Databases, REST APIs, APIs, Unit Testing, Web Development, DevOps, JSON, Java
Software Developer
2009 - 2009
Rise FM
- Created interactive banners for the company's website.
- Executed the main development in Flash (ActionScript), HTML, CSS, and PHP.
- Collected reviews and feedback from the viewers of the website.
- Maintained specific parts of the website based on the reviews.
- Held this summer position while attending high school.
Technologies: PHP, CSS, HTML, REST APIs, APIs, Unit Testing, Web Development, DevOps
Experience
DrBartha Toys: Software-enabled Coding Bricks for Kids
https://drbartha.comDrBartha Toys is an innovative coding system designed to introduce children as young as four to programming concepts through tangible play. The system utilizes smart, magnetic bricks (each representing a coding instruction such as loops, conditionals, or variables) that interlock to form executable programs. These sequences are activated on a companion device called the CodePad, which provides real-time visual feedback via an integrated display and RGB LEDs. This hands-on approach encourages experimentation, logical thinking, and debugging, making coding accessible and engaging for early learners. The project was successfully funded on Kickstarter on March 27, 2025, and late pledges are still available for those interested in supporting or acquiring the product.
Colorgram
https://github.com/denesbartha/ColorgramWhile working at the National University of Singapore, one of my projects was to create a more efficient representation of the Succinct Colored de Bruijn Graph data structure used for DNA assembly, compression, bubble calling, and to detect variations between individuals of a population.
Reconstruction of Rooted Directed Trees
https://github.com/denesbartha/RRDTWhile working on my Ph.D., I was mostly concentrating on problems of Statistical Bioinformatics. One particular problem was how to reconstruct tree graph structures from given frequencies of subgraph information. I gave a concrete algorithm for the rooted directed trees' problem and published my results in a paper.
Tree Graph Labeling
https://github.com/denesbartha/tree-graph-labelingFor my Master's thesis, I needed to use an efficient tree labeling algorithm. Because at the time the currently available algorithms were mostly theoretical (without any libraries), I have decided that I give a concrete solution to the problem. First I implemented my algorithm in C++ and then I gave an alternative implementation in Python.
Education
2014 - 2019
Ph.D. in Computer Science
Eötvös Loránd University - Hungary
2012 - 2014
Master's Degree in Computer Science
Eötvös Loránd University - Hungary
2009 - 2012
Bachelor's Degree in Computer Science
Eötvös Loránd University - Hungary
Certifications
MAY 2017 - PRESENT
Associate Android Developer
DECEMBER 2015 - PRESENT
Foundation Certificate in Software Testing
ISTQB
JUNE 2012 - PRESENT
Software Information Technologist
Eötvös Loránd University
Skills
Libraries/APIs
NumPy, Scikit-learn, TensorFlow, PyTorch, Pandas, Google APIs, REST APIs, OpenCV, OpenAI API, Stripe, PySpark, Sage, Keras, XGBoost, Puppeteer, Google Maps, jQuery
Tools
BigQuery, Git, PyCharm, CLion, Sublime Text 3, You Only Look Once (YOLO), ChatGPT, Pytest, DeepSeek, AI Prompts, Claude Code, Sublime Text, Maple, MATLAB, Tableau, AutoML, Cloud Dataflow, Apache Airflow, Terraform, Microsoft Power BI, Looker, Blender, Google Analytics
Languages
Python, C++, SQL, C, R, MicroPython, HTML, CSS, PHP, Assembly, Java, C#, Rust, JavaScript, Dart, TypeScript
Paradigms
Unit Testing, ETL, DevOps, Serverless Architecture, Scrum, Software Testing, Testing
Platforms
Google Cloud Platform (GCP), Linux, Raspberry Pi, Docker, Vertex AI, Ubuntu, Android, Jupyter Notebook, Amazon Web Services (AWS), Kubeflow, Kubernetes, Mixpanel, Firebase
Storage
Databases, JSON, Data Pipelines, PostgreSQL, Redis, Data Lakes, Google Cloud, Graph Databases, PL/SQL, MySQL
Frameworks
OAuth 2, Flask, Boost, Django, Android SDK, Flutter
Industry Expertise
Banking & Finance, Bioinformatics, Healthcare
Other
Artificial Intelligence (AI), Machine Learning, Deep Learning, Machine Learning Operations (MLOps), Data Science, Data Analysis, Data Scraping, Statistical Analysis, Statistics, Statistical Data Analysis, Data Analytics, Mathematical Statistics, Prompt Engineering, Architecture, Analytics, Performance, Chatbots, Natural Language Processing (NLP), Computer Vision, ESP32, Large Language Models (LLMs), Hardware Development, PCB Design, Generative Artificial Intelligence (GenAI), Data Visualization, Data Engineering, Predictive Analytics, Back-end, LangChain, AI Chatbots, FastAPI, Optical Character Recognition (OCR), Retrieval-augmented Generation (RAG), Agentic AI, Model Tuning, Object Detection, Hugging Face, Large Language Model Operations (LLMOps), APIs, Looker Studio, Statistical Modeling, Forecasting, Recommendation Systems, Fine-tuning, Open-source LLMs, CI/CD Pipelines, Full-stack Development, Minimum Viable Product (MVP), Fintech, Finance, Education, Statistical Methods, Google BigQuery, CTO, OpenAI, Pattern Recognition, Predictive Modeling, Deep Reinforcement Learning, Reinforcement Learning, Pricing, Pricing Models, AI Agents, Model Evaluation, Model Deployment, Model Monitoring, BERT, Language Models, Data Build Tool (dbt), Google Colaboratory (Colab), Convolutional Neural Networks (CNNs), Recurrent Neural Networks (RNNs), Sensor Data, IoT Protocols, Fivetran, Time Series Analysis, Electrical Engineering, 3D CAD, Vector Databases, YOLOv5, YOLOv8, Algorithms, Llama 3, Bokeh, Web Development, Digital Signal Processing, A/B Testing, Embedded Systems, Firmware Development, Universal Asynchronous Receiver/Transmitter (UART), I2C, Bluetooth Low Energy (BLE), Hardware Prototyping, Product Development, Small Language Models (SLMs)
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