Vladimir Jednak, Developer in Belgrade, Serbia
Vladimir is available for hire
Hire Vladimir

Vladimir Jednak

Verified Expert  in Engineering

Software Developer

Belgrade, Serbia
Toptal Member Since
June 18, 2020

Vladimir has over a decade of experience in business intelligence, databases, data warehouses, reporting solutions, development, architecture, and consultancy; including having worked on the complete lifecycle of BI/DWH solutions. Vladimir is passionate about database optimization and query tuning and is constantly searching for ways to improve processes.



Preferred Environment

Cognos 10, QlikView, SQL Server Integration Services (SSIS), Microsoft SQL Server

The most amazing...

...project I've done is a CDC (change data capture) solution created in SSIS.

Work Experience

Power BI Expert

2020 - PRESENT
Fortune 100 North American Construction Equipment Manufacturer (via Toptal)
  • Created interactive dashboards and reports in Power BI. Created advanced measures using DAX language.
  • Worked on data manipulation using Power Query. Created star schema as a reporting model.
  • Used data sources for Power BI: Oracle database, Excel files, Google Analytics.
Technologies: Data Modeling, DAX, Star Schema, Power Query M, Power Query, Microsoft Power BI

Data Warehouse Architect

2019 - PRESENT
Spartan Race Inc (via Toptal)
  • Created a DWH model using the Data Vault model.
  • Created a data mart model for reporting with the star schema.
  • Wrote ETL/SQL scripts.
  • Created metadata tables for configurations and mapping tables for data load and calculations.
  • Developed visualizations with Looker.
Technologies: Looker, PostgreSQL

Business Intelligence Consultant

2019 - PRESENT
DataClue GmbH (Freelance)
  • Created a data mart model for financial reporting.
  • Developed ETL/SQL procedures.
  • Developed visualizations with Power BI and DAX calculations.
  • Implemented time comparison calculations, and calculations for quantity, product mix, and price impact on revenue and material costs.
Technologies: Microsoft Power BI, Microsoft SQL Server

Business Intelligence Solution Manager

2017 - 2019
SR Technics Services
  • Developed BI solutions with QlikView and SAP Bex Tools.
  • Followed and enhanced SAP BW and QlikView load procedures.
  • Monitored and upheld data quality in SAP BW and QlikView process.
Technologies: Tools, SAP, SAP Business Warehouse (BW), QlikView

Freelance Senior SQL Developer

2016 - 2019
Datasport, Ltd. (via An Online Freelance Agency)
  • Wrote an SQL ranking calculation algorithm of athletes in competitions.
  • Optimized the database and query tuning.
  • Provided SQL support for live events.
Technologies: Microsoft SQL Server

Freelance Senior BI Developer

2016 - 2017
Multibase (via An Online Freelance Agency)
  • Developed and enhanced BI solutions.
  • Wrote reports using Microsoft Reporting Services and Microsoft Excel.
  • Implemented a DWH system using the data vault model.
Technologies: SQL Server Reporting Services (SSRS), SQL Server Integration Services (SSIS), Microsoft SQL Server

Senior Officer | DWH and BI Architect

2012 - 2017
Addiko Bank a.d. Beograd
  • Implemented a banking data warehouse and reporting system (Temenos T24, Informatica PowerCenter ETL, and Cognos).
  • Credited and deposited a portfolio and other analytics reports with a market interest method calculation for the financial control department.
  • Managed and architected the HBSE retail risk data infrastructure, including the risk data mart and reporting.
  • Developed the COGNOS planning tool for the risk department.
  • Implemented dimensional and data (Erwin) modeling.
  • Defined the models (data warehouse and data mart designs).
  • Worked on ETL development (SSIS and Informatica PowerCenter), including reporting and ETL automation and optimization.
Technologies: IBM Db2, SQL Server Reporting Services (SSRS), IBM Cognos, Cognos 10, SQL Server Integration Services (SSIS), Microsoft SQL Server

Senior BI Developer

2012 - 2012
IT Excellence
  • Optimized the ETL process (SSIS) and developed automated SSIS packages.
  • Developed a CDC (change data capture) system and surrogate key architecture.
  • Improved the ETL and SQL calculations execution time.
Technologies: SQL Server Integration Services (SSIS), Microsoft SQL Server

Independent Software Developer

2010 - 2012
Asseco SEE
  • Implemented a risk management application: IK Banka Zenica, Sinergija Banja Luka.
  • Built an anti-money laundering module and a provision calculation application for Investiciono Komercijalna Bank Zenica, Bosnia and Herzegovina.
  • Developed and implemented a past-due scoring category for Univerzal Banka Beograd, Procredit Banka.
  • Wrote the reports for several domestic banks: Komercijalna Banka Beograd, Privredna Banka Beograd, Marfin Banka, Univerzal Banka, Agro Banka, and more.
Technologies: T-SQL (Transact-SQL), Microsoft SQL Server

BI Software Developer

2008 - 2010
Asseco SEE
  • Developed a business intelligence system for several banks in Serbia and Macedonia.
  • Wrote reports using Microsoft Reporting Services (SSRS) and Microsoft Excel.
  • Modeled, designed, and implemented a system to automatically generate reports.
  • Tested reports with the business section of the banks.
  • Provided support to the IT and business sections of the banks.
Technologies: SQL Server Integration Services (SSIS), Microsoft SQL Server, T-SQL (Transact-SQL), SSAS, SQL Server Analysis Services (SSAS)

DWH/CDC Project

Here, I developed a CDC (change data capture) system and surrogate key architecture using SSIS.
2008 - 2010

Master's Degree in IT (Information Systems and Technology)

University of Belgrade - Belgrade, Serbia

1997 - 2008

Bachelor's Degree in IT ( Information Systems and Technology)

University of Belgrade - Belgrade, Serbia


Microsoft Certified: Azure Data Fundamentals



Microsoft Certified: Azure Fundamentals


MAY 2020 - MAY 2022

Microsoft Certified: Data Analyst Associate



Google Cloud Certified — Associate Cloud Engineer

Google Cloud


Automation Anywhere Certified Advanced RPA Professional

Automation Anywhere


Microsoft Certified IT Professional: Database Developer 2008



Microsoft Certified IT Professional: Business Intelligence Developer 2008



Microsoft Certified Technology Specialist: SQL Server 2008, Database Development



Microsoft Certified Technology Specialist: SQL Server 2008, Business Intelligence Development and Maintenance



IBM Cognos, Microsoft Power BI, SQL Server BI, Power Query, Looker, BEx Reporting, SSAS


SQL, T-SQL (Transact-SQL), Stored Procedure, Power Query M


Database Design, Business Intelligence (BI), Database Development, ETL, ETL Implementation & Design, OLAP


Microsoft BI Stack, Qlik, QlikView, Azure


PL/SQL, SQL Server Integration Services (SSIS), ANSI SQL, SQL Performance, Databases, SQL Stored Procedures, SQL Views, SQL Functions, Database Modeling, SQL Server Reporting Services (SSRS), SQL Server DBA, OLTP, Microsoft SQL Server, PostgreSQL, SQL Server Analysis Services (SSAS), IBM Db2, Azure SQL Databases, Azure SQL


Cognos 10, PL/SQL Tuning, Query Optimization, Data Visualization, Data Warehousing, Data Warehouse Design, Requirements & Specifications, MCSE | Business Intelligence, ETL Development, BI Reports, Data Reporting, Reporting, Reports, Data Engineering, Data Modeling, DAX, Star Schema, SAP Business Warehouse (BW), SAP, Tools, Azure Data Factory

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.


Share your needs

Discuss your requirements and refine your scope in a call with a Toptal domain expert.

Choose your talent

Get a short list of expertly matched talent within 24 hours to review, interview, and choose from.

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