Jurijs Jefimovs
Data Engineer and Developer
Location
Riga, Latvia
Toptal Member Since
November 24, 2020
Jurijs is an experienced Business Intelligence (BI) engineer with 14 years of experience building data warehouses (DWH) and BI applications. He can create a self-service BI environment for your organization from scratch, including building DWH, BI applications, and training for business users. He has strong experience with various relational, non-relational databases (NoSQL), and distributed systems.
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Luminor Bank AS
Performance Tuning, Performance Analysis, Cloud Architecture...
LeoVegas Group
Performance Analysis, Google Cloud Platform (GCP), APIs...
Betsson Group
SQL Performance, Performance Tuning, Performance Analysis, APIs...
Experience
ETL Development - 13 yearsData Warehouse Design - 12 yearsDimensional Modeling - 12 yearsTableau - 5 yearsQlikView - 3 yearsQlik Sense - 1 yearGoogle Data Studio - 1 yearGoogle BigQuery - 1 yearLocation
Availability
Part-time
Preferred Environment
PL/SQL, Talend ETL, ELK (Elastic Stack), MongoDB, PostgreSQL, Google BigQuery, Google Data Studio, Qlik Sense, QlikView, Tableau
The most amazing...
...thing I've rolled out was self-service BI with environment set up, data warehousing, ETL development, dimensional modeling, app development, and user training.
Work Experience
2018 - PRESENT
Unit Manager of Data Platform Unit/Service Area Delivery Manager
Luminor Bank AS
- Released the first version of the transaction search which provides search capabilities for interactive account statement service to end-users of the internet bank.
- Migrated customer transaction history from the old core system into a new data platform.
- Introduced pub-sub message delivery semantics for data integration between backend components.
- Built an internal team that took over the development of a data platform from an external consultancy.
- Supervised and coordinated the implementation of functional and non-functional requirements.
- Designed and defended various solution proposals in front of the enterprise architecture committee.
Technologies: Performance Tuning, Performance Analysis, Cloud Architecture, Amazon Web Services (AWS), APIs, Business Intelligence (BI), Streaming, Requirements Analysis, Business Analysis, Impact Analysis, Big Data Architecture, Big Data, Data Visualization, Remote Team Leadership, Remote Work, Team Leadership, Leadership, ETL Implementation & Design, Elasticsearch, NoSQL, Database Architecture, Data Architecture, Data Pipelines, Data Lakes, Data Engineering, Data Modeling, Database Modeling, SQL, Kafka Streams, Kibana, Amazon EKS, Apache NiFi, Amazon S3 (AWS S3), Amazon MSK
2017 - 2020
BI Engineer
LeoVegas Group
- Developed various BI applications with QlikView and Tableau for business areas such as marketing, customer acquisition, CRM, responsible gaming, payments, and finance.
- Created and supported various automated reports with Qlik NPrinting.
- Developed ETL and data marts with QlikView and jobs orchestration with QlikView Publisher.
- Built the DWH on Google Cloud Platform (dimensional modeling).
- Developed a BI application that helps to configure payment providers' pricing models and automatically calculate commissions. Developed with Google Sheets (configuration tool), Google Big Query (ETL), and Data Studio (reporting).
Technologies: Performance Analysis, Google Cloud Platform (GCP), APIs, Business Intelligence Training, Business Intelligence (BI), Requirements Analysis, Business Analysis, Impact Analysis, Analytical Thinking, Analytics, Analytical Dashboards, Visualization Tools, Visualization, Dashboard Design, Dashboards, Dashboard Development, Big Data, Data Visualization, Team Leadership, Remote Work, Database Architecture, Data Architecture, Data Pipelines, Data Lakes, Database Modeling, Data Modeling, SQL, ETL Implementation & Design, ETL, Google Data Studio, Google BigQuery, Tableau, Qlik NPrinting, QlikView
2016 - 2017
BI Data Engineer
Betsson Group
- Implemented a self-service BI environment with Qlik Sense—from setting up the environment, data modeling, development of applications, and user training.
- Developed various BI applications such as CLV for marketing and customer classification with Qlik Sence.
- Created the POC of real-time analytics with ELK (Elastic stack).
- Developed the POC of data analytical layer for a big data platform to accelerate data queries speed with Jethro data.
Technologies: SQL Performance, Performance Tuning, Performance Analysis, APIs, Business Intelligence Training, Business Intelligence (BI), Analytical Dashboards, Analysis, Analytics, Visualization Tools, Visualization, Dashboard Development, Dashboards, Dashboard Design, Big Data, Data Visualization, ETL Implementation & Design, Elasticsearch, NoSQL, Data Architecture, Data Pipelines, Data Lakes, Data Engineering, Data Modeling, SQL, Kibana, Kibi, Tableau, Microsoft SQL Server, ELK (Elastic Stack), Jethro, Apache Hive, QlikView, Qlik Sense
2015 - 2016
Lead Software Developer
Intrum Justitia
- Developed an analytical layer on top of the Big Data (Cloudera CDH) with the help of Apache Hive (ETL), Apache Impala (query engine), and Tableau (BI application layer).
- Built a consolidated dimensional model that brought data from different sources into a single data model that fit many business reporting needs.
- Introduced self-service BI to business users. Participated in many internal conferences in different offices around the EU to promote self-service BI with Tableau.
Technologies: Performance Tuning, SQL Performance, Performance Analysis, APIs, Business Intelligence Training, Business Intelligence (BI), Analytical Thinking, Analysis, Analytics, Visualization Tools, Dashboards, Analytical Dashboards, Visualization, Dashboard Development, Dashboard Design, Big Data, Data Visualization, ETL Implementation & Design, NoSQL, Database Architecture, Big Data Architecture, Data Architecture, Data Pipelines, Data Lakes, Data Engineering, Data Modeling, Database Modeling, SQL, Apache Kylin, Apache Hive, Apache Impala, Tableau
2009 - 2015
Systems Analyst
Idea Port Riga
- Developed and maintained DWH, ETL, and BI application processes for the insurance, telco, and pharmacy retailer companies.
- Customized CRM system to fix reporting data gaps and improve ETL processes (CDC).
- Built a data archiving tool to offload historical data from CRM to improve CRM's performance, which helped to decrease customer service response time.
- Developed POC of fraud detection BI application, which helped find fraudulent cases and analyze the reasons behind insurance claims.
- Created the POC of a product recommendation engine for pharmacy retailers, which could increase sales by offering similar products based on transactional data.
Technologies: SQL Performance, Performance Tuning, APIs, Business Intelligence Training, Business Intelligence (BI), Visualization Tools, Visualization, Dashboard Design, Dashboard Development, Dashboards, Data Visualization, ETL Implementation & Design, Database Architecture, Data Architecture, Data Pipelines, Data Modeling, Database Modeling, SQL, Siebel CRM, Oracle Data Miner, SQL Server Reporting Services (SSRS), SQL Server Analysis Services (SSAS), SQL Server Integration Services (SSIS), Microsoft SQL Server, Oracle Warehouse Builder (OWB), Informatica PowerCenter, IBM Cognos Business Intelligence, Oracle RDBMS, Oracle BI EE 11g
2007 - 2009
Securities and Financial Market Department, Analyst Programmer
Rietumu Bank
- Built the customer investment portfolio performance report for customers.
- Created customer account statements and other regulatory reports automation.
- Developed the automated generation of customers' account statements and send-outs by email.
Technologies: SQL Performance, Performance Tuning, Performance Analysis, APIs, Business Intelligence (BI), Data Visualization, ETL Implementation & Design, Database Architecture, Data Architecture, Data Pipelines, Data Modeling, Database Modeling, SQL, Bloomberg API, Excel VBA, Microsoft Excel, Microsoft Access, T-SQL (Transact-SQL), Microsoft SQL Server, Crystal Reports
2006 - 2007
Senior Developer
Accenture
- Developed the integration layer between legacy systems and Oracle Siebel CRM (Java).
- Customized various Siebel CRM applications for clients.
- Improved performance of Siebel CRM system for a few clients by reviewing and refactoring custom scripts.
Technologies: Performance Tuning, Performance Analysis, APIs, Data Modeling, Database Architecture, SQL, Java, Siebel CRM
Experience
Data Streaming Platform
I led and supervised the implementation of the data streaming platform for daily banking needs (end users/retail). We have successfully released the first version of data streaming platform services and created a good foundation for future services that can recommend and communicate the right information at the right time to customers. This can potentially increase user engagement and the usage of banking products and services.
Self-service BI Environment
I've introduced a self-service BI environment inside a company that helped reduce reports and data analyses delivery time. First, I've set up the Qlik Sense environment and build data marts used by business users for ad hoc report creation and sharing. Then, I've trained business analysts on how to create data marts of their domain areas inside Qlik Sense to help faster react to business analytical needs.
Analytical Layer on Top of Big Data
Designed and implemented an analytical layer on top of the Hadoop raw data, which allowed to build a flexible BI application layer to satisfy the company's reporting and ad hoc query needs. Instead of building custom reporting solutions with map-reduce, I've proposed making a dimensional model (star schema) on top of the Hadoop with Hive's help as the ETL engine and Impala for accelerating queries over Hive metadata. I also introduced self-service BI with Tableau. This was completely my initiative, which I completed in 2015 when people had zero trust in such technologies.
Tableau Public Profile
https://public.tableau.com/profile/jurijs.jefimovs#!/Tableau public profile where you can see examples of Tableau applications/dashboards. There you can find examples of interactive dashboards, geospatial charts, Sankey diagrams, applications build using public data sources such as GDELT, Riga Open Data (new-birth statistics), Kaggle competition, and more.
Skills
Languages
SQL, T-SQL (Transact-SQL), Excel VBA, Java, R, Python, JavaScript
Tools
Tableau, Apache Impala, Informatica PowerCenter, Oracle Warehouse Builder (OWB), Qlik Sense, ELK (Elastic Stack), Talend ETL, Apache NiFi, Amazon EKS, Kafka Streams, Siebel CRM, Crystal Reports, Microsoft Access, Microsoft Excel, Microsoft Power BI
Paradigms
Database Design, Dimensional Modeling, ETL, ETL Implementation & Design, Requirements Analysis, Business Intelligence (BI), Data Science
Storage
Database Architecture, Database Modeling, PL/SQL, Apache Hive, Data Lakes, Data Pipelines, NoSQL, Elasticsearch, SQL Performance, PostgreSQL, MongoDB, Amazon S3 (AWS S3), Microsoft SQL Server, Oracle RDBMS, SQL Server Integration Services (SSIS), SQL Server Analysis Services (SSAS), SQL Server Reporting Services (SSRS)
Other
Data Warehouse Design, ETL Development, Data Modeling, Data Architecture, Data Visualization, Dashboard Development, Dashboards, Dashboard Design, Visualization, Visualization Tools, Analytical Dashboards, Analytics, Analytical Thinking, Analysis, Impact Analysis, Business Analysis, Business Intelligence Training, Google Data Studio, Google BigQuery, Data Engineering, Performance Analysis, Amazon MSK, Jethro, Apache Kylin, IBM Cognos Business Intelligence, Oracle Data Miner, Performance Tuning, Big Data Architecture, Leadership, Team Leadership, Remote Work, Remote Team Leadership, NiFi, IT Project Management, Big Data, Streaming, APIs, Cloud Architecture, Open Data, Data Transformation
Platforms
QlikView, Qlik NPrinting, Oracle BI EE 11g, Apache Kafka, Amazon Web Services (AWS), Google Cloud Platform (GCP)
Libraries/APIs
Bloomberg API, Spark ML
Industry Expertise
Project Management
Education
2002 - 2009
Master's Degree in Computer Science
Transport and Telecommunication Institute - Riga, Latvia
Certifications
MARCH 2019 - PRESENT
MongoDB Performance
MongoDB University
SEPTEMBER 2017 - PRESENT
Google Cloud Platform Big Data and Machine Learning
Coursera
JANUARY 2016 - PRESENT
Tableau Advanced Trainings
Udemy
AUGUST 2015 - PRESENT
Big Data XSeries
edX
MAY 2015 - PRESENT
Data Science Specialization
Coursera