Nac Stoklas
Verified Expert in Engineering
Data Scientist and Developer
Nac is a data scientist who builds efficient ML and data pipelines. He is experienced in developing regression and classification models, scalable data pipelines, and presenting data in a way that offers the most insight. He has judged ML competitions and has participated in hackathons while helping host them. The wide range of projects Nac has worked on helps him understand his clients' needs, exceeding their expectations.
Portfolio
Experience
Availability
Preferred Environment
Jira, Slack, Visual Studio Code (VS Code), SQL Server Management Studio (SSMS), MacOS, IntelliJ IDEA
The most amazing...
...thing I've built is a cloud-based ML pipeline that can forecast sales for hundreds of thousands of items and set optimal stock levels in a matter of hours.
Work Experience
Data Scientist
Outbrain
- Improved internal tooling is used for validating features for models used in production that make over a billion predictions daily.
- Reworked parts of the systems that directly impact the most important business KPIs leading to a 5% increase in revenue (AB tested).
- Improved existing models by leveraging unused past data with the help of amazing colleagues to increase spending, revenue, and ex-tac by a significant margin.
Data Scientist
BE-terna
- Built a pipeline for automated forecasting and scheduling of item deliveries for major retailers in the Adriatic and DACH regions.
- Built a pipeline that makes and predicts sales for hundreds of thousands of items within a few hours using Databricks and the accompanying ecosystem on Azure. This resulted in a significant decrease in time for predictions for our clients.
- Developed an algorithm to convert data from graphs to BI-friendly relational format (recursion in production, achievement unlocked).
- Exposed APIs that allow forecasting of many different time series types and integrate seamlessly into many large ERP systems.
- Built custom extensions for Qlik Sense and a product backlog item (PBI) connected to ERP systems, making the clients' daily workflow faster by over 65%.
- Worked on time series analysis, detecting outliers, seasonal patterns, and more for a major pharmaceutical distributor.
Data Scientist
Adacta d.o.o.
- Built a basket analysis case for a chain of highway stores using association rules and prepared a dashboard for it.
- Worked with clients to port and upgrade multiple applications from QlikView to Qlik Sense.
- Built ETL pipelines that supply dashboards with hourly data updates used by multiple departments in a large Slovenian company.
Python Developer
Faculty of Computer and Information Science - Ljubljana
- Helped develop object detection for ski jumps using up to three cheap cameras.
- Contributed to building the streaming pipeline for live measuring of ski jump length.
- Developed an algorithm for automatically measuring ski jump distance length using environmental factors.
IT Support
Maksim d.o.o.
- Built a pipeline and services related to scoring and evaluating satisfaction surveys.
- Helped the IT with updating software within the company and helping with the digital transformation.
- Supported in-house engineers with time-sensitive complex IT tasks.
Experience
Automated Scheduler and Stock Optimizer
The solution segments items into different categories and makes predictions for scheduling optimal times considering deliveries, current stock levels, vendor preferences, and cargo requirements like shipping and truck space.
I built most of the scalable data pipeline and made prediction models. I also developed most of the supporting DevOps pipelines for CI/CD.
I've used cloud technologies such as Azure functions, Data Lake, Blob storage, Databricks, and others.
API Portal One Stop Shop for Developers
Businesses use it daily to get high accuracy, low latency forecasts for their business needs. I also built several APIs on offer, including multiple methods for different types of forecasts, such as weather-based, window methods, statistical methods, and boosting-backed methods.
Basket Analysis for a Major Retailer
I also built a custom extension that allowed for write-back functionality within Qlik Sense, used for the dashboard.
Neo4j | Qlik Sense Connector
It was integrated with Qlik Sense for a major Slovenian retailer to analyze their graph database data using standard BI tools.
DevOps Pipeline for Automated Product Delivery
It automatically tests the code, builds artifacts, and deploys them on production clusters (Spark and Databricks), updating libraries and code when there is the least customer traffic.
Evaluation Dashboard in Qlik Sense
QlikView App Ported to Qlik Sense
It entailed finding equivalents for many major QlikView features in Qlik Sense, adjusting the ETL so that it finds into the Qlik Sense script editor, and adjusting the visuals to fit into the newer engine.
Forecasting API
This supports many parameters, such as weather and holidays (for ISO country names) and more fine-tuning for automated parameter selection. It can be easily embedded in major ERP solutions—FO, BC, NAV, and Infor. It offers support for statistical algorithms, boosting methods, and classical ML.
Object Detection for Ski Jumps
Skillset
Languages
Python, SQL, JavaScript, HTML, TypeScript, Batch, Go
Libraries/APIs
Pandas, Azure API Management, NumPy, Scikit-learn, REST APIs, Azure Blob Storage API, XGBoost, CatBoost, Keras, PySpark, OpenCV, Spark ML, PyQt 5
Tools
Qlik Sense, Postman, Azure Machine Learning, Jira, Slack, Microsoft Teams, Microsoft Power BI, Microsoft Excel, Tableau, Azure Key Vault, Azure Application Insights, Azure DevOps Services, Docker Compose, Kibana, BigQuery, IntelliJ IDEA, Apache Airflow
Paradigms
Data Science, ETL, Business Intelligence (BI), REST, DevOps, Azure DevOps, Windows App Development, Desktop App Development
Platforms
Windows, Jupyter Notebook, Databricks, Azure, Azure Functions, Azure SQL Data Warehouse, QlikView, Docker, Amazon, Visual Studio Code (VS Code), MacOS, Dedicated SQL Pool (formerly SQL DW)
Other
Classification, Regression Modeling, Software Engineering, Machine Learning, Azure Databricks, Artificial Intelligence (AI), Time Series, Time Series Analysis, APIs, Data Engineering, ETL Tools, Data Analysis, Complex Data Analysis, Data Analytics, Simulations, Dashboard Design, Data Cleansing, Big Data, Analytics, Data Visualization, Data Modeling, Distributed Systems, Azure Data Lake, SOAP, Deep Neural Networks, Computer Vision, PBI Tools, Neural Networks, IIS, Web Scraping, Statistical Modeling, Association Rule Learning, CI/CD Pipelines, Data Quality Analysis, Data Cleaning, Weather, Videos, Predictive Modeling, Forecasting
Frameworks
Django, Spark
Storage
PostgreSQL, Azure SQL, Data Pipelines, Azure Blobs, Databases, Azure SQL Databases, SQL Server Management Studio (SSMS), PostgreSQL 10, Neo4j, Graph Databases, Azure Cloud Services
Education
Master's Degree in Computer Science
University of Ljubljana - Ljubljana, Slovenia
Certifications
Microsoft Certified | Azure Data Fundamentals
Microsoft
Microsoft Certified | Azure AI Fundamentals
Microsoft
Microsoft Certified | Power Platform Fundamentals
Microsoft
Microsoft Certified | Azure Data Scientist Associate
Microsoft
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