Kalin Stefanov - Sr Data Engineer / Architect

Geneva, Switzerland

Experience

Dec 2024 - Present

1 year 2 months

Netherlands

Sr Data Engineer / Architect

Samsung Logistics

Architected and implemented a structured three-layer enterprise data warehouse model in Azure, establishing a robust and scalable data environment.
Migrated legacy stored procedures to streamlined Azure Data Factory (ADF) pipelines, enhancing data processing efficiency.
Introduced comprehensive Git-based source control, ensuring rigorous version management and collaborative development practices.
Established automated data quality frameworks with proactive monitoring and alerting, significantly improving data integrity and reliability.
Spearheaded the design of an enterprise data model, enabling a self-service BI environment that empowered business teams with advanced analytics capabilities.
Developed and delivered insightful dashboards and reports in Power BI, transforming raw data into actionable business insights.
Technologies: Azure Data Factory (ADF), Azure, MS-SQL, DataVault 2.0, Git, Power BI, data quality automation, Agile/Scrum, data modeling, self-service BI, stakeholder management.

Mar 2024 - Dec 2024

10 months

Amsterdam, Netherlands

Sr Data Engineer / Manager

Booking.com

Designed and built data marts (models) and pipelines for structured data in the data lake, with a focus on supply chain management (suppliers) and marketing projects.
Led a migration team (4 FTE) to convert existing ETL pipelines to a Snowflake environment, including data modeling.
Developed complex data pipelines in PySpark, Python, Airflow and HQL (Hadoop Hive SQL) for large-scale data processing, providing strong technical and architectural expertise.
Worked in an Agile Scrum team with over 30 multidisciplinary team members, ranging from business analysts to data scientists.
Technologies: Airflow, DBT, SQL, Python, Spark, Snowflake, Grafana, Visual Studio Code, Hadoop, Perl, Bash UNIX scripting, stakeholder management.

Feb 2023 - Dec 2023

11 months

The Hague, Netherlands

Sr Data Engineer / Architect

ANWB LLC

Acted as both Data Engineer and Solution Architect, leading the reengineering of data marts within the Road Assistance department to align with the strategic migration to a Snowflake environment.
Directed the reverse-engineering of the Customer Demand List (CDL) to optimize performance, combining strong technical proficiency and architectural oversight.
Completed the implementation phase and departed due to budgetary constraints after establishing a robust foundation for the department’s data operations.
Technologies: Snowflake SQL, Azure, MS-SQL, SSIS ETL, Upsolver, Jira, Agile/Scrum, DevOps, DataVault 2.0, QlikView, Power BI, DataHub, data quality automation, data science, hackathons, AI/ChatGPT.

May 2019 - Jan 2024

4 years 9 months

New York, United States

Sr Data Engineer

DaisTech LLC

Worked for 4.5 years for several US companies as a self-employed data engineer.
Gained solid knowledge and experience of cloud server technologies, Python programming language, data orchestration tools and big data.

Jul 2011 - May 2019

7 years 11 months

Amsterdam, Netherlands

Data Engineer & BI/DWH Consultant (self-employed)

Dais

Worked for 8 years on a contracting basis for numerous organizations in the Netherlands.
Delivered high-quality services for improving clients’ data structures, information systems and business management.

Jan 2011 - Aug 2012

1 year 8 months

Amsterdam, Netherlands

Business Intelligence Consultant / Data Engineer

ING Bank Plc.

Served as a Business Intelligence Consultant and Data Engineer across several projects within ING Bank.
Contributed to data warehouse design, data migration, analytics and CRM initiatives.

Sep 2008 - Aug 2011

3 years

Amsterdam, Netherlands

Data Engineer & BI/DWH Consultant

Ordina

Data Engineer and Business Intelligence Consultant within the VisionWorks team.
Participated in several client projects focused on customer intelligence, CRM and data warehousing.

Jul 2007 - Sep 2008

1 year 3 months

Amersfoort, Netherlands

MS BI Developer

BI4U Ltd.

Developed a generic business intelligence data warehouse solution for the healthcare industry in the Netherlands.
Technologies: SQL Server 2005, SSRS, SSIS, SSAS, SSMS, healthcare (Zorg), DBC, Intelligence Factory, Kaizen, lean management.

Feb 2007 - Jul 2007

6 months

's-Hertogenbosch, Netherlands

Product Consultant

BWise Ltd.

Implemented the BWise risk management product suite at various organizations.
Worked on governance, risk and compliance solutions.
Technologies and domains: Basel II, SOX, ITIL, Crystal Reports.

Nov 2006 - Jan 2007

3 months

Amsterdam, Netherlands

Sybase Developer

ING Bank Plc.

Worked at the Corporate Credit Risk Management department as a SQL programmer (Sybase) and technical analyst.
Supported risk modeling and reporting for credit risk metrics.
Technologies and domains: PD (Probability of Default), EAD (Exposure at Default), LGD (Loss Given Default), risk modeling, Sybase SQL, Perl.

Jan 2006 - Aug 2006

8 months

Halfweg, Netherlands

Graduation Intern

WilroffReitsma Ltd.

Built a reporting system from scratch for finance and operations.
Technologies: DTS, MS-SQL, SSRS, SQL Server 2000.

Mar 2003 - Sep 2003

7 months

Etten-Leur, Netherlands

Intern

ABB Benelux Plc.

Conducted individual research on software integration within the organization.

Boston, United States

Sr Data Engineer

Boston Consulting Group

Reverse-engineered Oracle DI and SQL Server pipelines to Snowflake SQL.
Re-implemented logic as data mart views in Snowflake and automated orchestration and feeding of solution pipelines through Fivetran.
Served as tech lead and liaison between business units and technical support during migration projects.
Technologies: Snowflake SQL, Fivetran, MS-SQL Server, MySQL, GitLab, PL/SQL, Oracle, SAP Enterprise, Slack, Jira.

Amsterdam, Netherlands

Regulatory Reporting Specialist

ING Bank Plc.

Redesigned and reworked a mis-performing regulatory reporting system.
Acted as Scrum Master and technical lead in SQL and reporting for regulatory domains.
Technologies and domains: IFRS 9, Liquidity Coverage Ratio (LCR), Oracle PL/SQL, SAP, Dutch National Bank (DNB), European Central Bank (ECB), MiFID II, FINREP, COREP.

Amsterdam, Netherlands

Data Warehouse Specialist / Project Manager

ING Domestic Retail Bank Plc.

Designed and developed a data warehouse solution for ING Retail SME customers.
Worked on data and information analysis, SME CRM, customer segmentation and proof-of-concept implementations.
Technologies: MS-SQL, data modeling, CloverETL, MySQL, Pentaho, Talend.

Amsterdam, Netherlands

BI / SQL / CRM Specialist / Data Mining & Analytics Consultant

ING Domestic Retail Bank Plc., Customer Intelligence Department

Worked on upgrading the Customer Intelligence platform.
Delivered BI, SQL and CRM solutions as well as data mining and analytics consulting.
Technologies: SAS, PL/SQL, multi-channel campaign management, CRM, Oracle, Tango, marketing intelligence.

Amsterdam, Netherlands

BI / SQL / CRM Specialist / Data Mining & Analytics Consultant

ING Domestic Retail Bank, Customer Intelligence Department

Contributed to the upgrade of the Customer Intelligence platform.
Provided BI, SQL, CRM and data mining expertise.
Technologies: SAS, PL/SQL, multi-channel campaign management, CRM, Oracle, Tango, marketing intelligence.

Amsterdam, Netherlands

Sr BI Developer

KASBANK Plc.

Implemented a data warehouse solution supporting custodial banking operations.
Led BI work within an Agile/Scrum framework.
Technologies and domains: MS-SQL, Kimball methodology, BI framework design, SSIS ETL, C#, ISIN, custodian banking.

Menlo Park, United States

Sr Data Engineer

Meta Platforms Inc. (Facebook)

Designed and developed multiple data marts and dashboards for the Infrastructure department in cooperation with data scientists.
Proactively identified usable data points to facilitate mitigation response times for on-call teams.
As an end-responsible tech lead, proposed, designed and developed an end-to-end solution including data analysis, data transformation logic, data pipelines, visualization, system testing, UAT and presentations to partners.
Technologies: Presto SQL, Unidash, Python, big data, data lake, Hive, on-call operations, infrastructure analytics.

The Hague, Netherlands

Sr MSBI Developer / Data Analyst / DWH Modeler

NIBC NV

Participated in more than 7 enterprise data projects in various roles including MSBI development, data analysis and data warehouse modeling.
Focus areas included regulatory reporting and data virtualization.
Technologies and domains: Anacredit, DGS, VIA, cost allocation models, data virtualization.

New York, United States

Sr Data Engineer

Newsela Inc.

Migrated the data warehouse for user activity tracking and product engagement from Amazon Redshift to Snowflake, loaded by Loome data streams.
Optimized performance of SnowSQL scripts, resulting in a 40% reduction in data processing expenses.
Introduced an automated data quality testing scheme to track and report anomalies based on recent record counts and calendar-based exceptions.
Technologies: Snowflake SQL, SOA, Python, Looker, Loome, Fivetran, Kinesis, Amazon Web Services (AWS), Redshift, JSON, enterprise data integration, data lake, data marts and data modeling.

Utrecht, Netherlands

Data Engineer / Marketing Software Integration Specialist

Rabobank Corp.

Worked on marketing software back-end integration within Rabobank CRM.
Implemented SmartFocus-based marketing campaign management.
Technologies: marketing campaign management, SAP, CRM, SQL, HP NeoView, SmartFocus.

Atlanta, United States

Sr Data Engineer

Randstad Technologies

As a technical lead, designed and created a dimensional enterprise data model, migrated data, built new data pipelines and data marts, performed quality assurance testing and managed code reviews and releases for billing, staff placements and customer domains.
Worked within an Agile/Scrum multidisciplinary team responsible for enterprise business intelligence.
Reverse-engineered Talend ETL pipelines to SQL and shifted to an ELT tech stack based on an internally developed system generating Apache Airflow code to process data on Google Cloud Platform (GCP) BigQuery.
Enhanced the internally developed code generation system to handle configurations.
Technologies: BigQuery, Python, Airflow, data marts, Spinnaker, GitLab, Talend, Oracle, SQL, SOA.

Hilversum, Netherlands

Open Source DWH Designer and Developer

SPIL Games LLC

Designed and developed an open source data warehouse as a proof-of-concept for online games portals.
Technologies: open-source BI, Pentaho, Google Analytics.

Wognum, Netherlands

Team Lead BI

Simon Loos Ltd.

Led the implementation of a data warehouse solution supporting transport and logistics operations.
Technologies and domains: MS-SQL, Kimball methodology, cost-effective planning, transport and logistics analytics, SSRS, Agile/Scrum.

Amersfoort, Netherlands

Senior Software Developer Sybase

Stater Plc.

Performed SEPA redesign and modification of a mortgage maintenance system.
Technologies and domains: Sybase, SQL, Uniface, VMS, SEPA, private mortgages, credit risk, direct debit batch processing, XML.

Antwerp, Belgium

Senior Microsoft BI Developer

Telenet Plc.

Upgraded the Network Capacity Data Warehouse for a telecommunications provider.
Technologies and domains: MS-SQL, VB.NET, data archiving, HFC networks, capacity planning, telecom.

Amsterdam, Netherlands

Data Warehouse Developer & Test Specialist

UWV

Developed ETL and reporting for the Polis+ system.
Performed data modeling and testing for social security and payroll-related data.
Technologies: MS-SQL, SSIS, SSRS, data modeling, PolisPlus, Policy Administration, Wage Tax Liability.

Amersfoort, Netherlands

Sr MS Developer

Volkswagen Pon Financial Services

Designed and developed a custom-made sensitive data anonymization tool.
Technologies: GDPR, MS-SQL, SSIS, C#, VB.NET.

Hilversum, Netherlands

Software Engineer SQL

WSW

Designed and developed a new software solution for real estate associations’ financial and business risk models.
Technologies and domains: S&P matrix, T-SQL, SSIS framework, data quality management (DQM), master data management (MDM), QlikView.

New York, United States

Sr Data Engineer

WarnerMedia (HBO)

Enabled marketing analytics by loading advertising data into Snowflake using data pipelines built with Apache Airflow, Python and SnowSQL.
Created a Python-based solution for automated data quality verification and alerting.
Re-engineered an existing data warehouse to a unified enterprise model to eliminate redundancy and promote reusability of conformed dimensions across department-specific data marts.
Provided guidance and mentorship to newly onboarded remote team members to decrease time to productivity.
Technologies: Snowflake, Python, GitHub, JSON, Airflow, data modelling, Agile/Scrum, team leadership.

Amsterdam, Netherlands

Data Analyst / Audit & Financial Data Validation and Test Specialist / SQL Server and SSIS Developer

WestlandUtrecht Bank Plc.

Managed data migration and transformation of ING Bank accounts to WestlandUtrecht Bank.
Performed data analysis, audit, financial data validation and testing.
Developed ETL processes using SQL Server and SSIS.
Technologies: MS-SQL, data migration, Europort+, ETL, Syntel, hash totals, conversion, data quality.

Alphen aan den Rijn, Netherlands

Marketing Intelligence Specialist

Wolters Kluwer Plc.

Worked on marketing intelligence initiatives using enterprise campaign and reporting tools.
Technologies: Unica, IBM, Cognos, Oracle, Informatica PowerCenter, campaign management.

Summary

Senior technical engineer with 15+ years of experience helping companies to structure and leverage business data and information management systems to drive decision-making.

Key strengths in business process consulting, data modeling and integration as well as data flow automation.

Certified as a SQL and Python developer. MSc in Business Management. Always taking ownership and shows leadership. Good in project management, stakeholder management and multi-disciplinary global teamwork.

Languages

Dutch

Native

English

Advanced

Education

Feb 2016 - Apr 2019

Open Universiteit

MSc in Business Process Management & IT (minor: Data Science & Analytics) · Business Process Management & IT · Amsterdam, Netherlands

Feb 2011 - Feb 2013

University of Amsterdam Business School

Pre-Master of Science in Business Studies · Business Studies · Amsterdam, Netherlands

Oct 2000 - Jul 2006

Hogeschool Inholland

Bachelor of Applied Science in Business Informatics · Business Informatics · Diemen, Netherlands

Certifications & licenses

SQL And Python Developer

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Experience

Sr Data Engineer / Architect

Samsung Logistics

Sr Data Engineer / Manager

Booking.com

Sr Data Engineer / Architect

ANWB LLC

Sr Data Engineer

DaisTech LLC

Data Engineer & BI/DWH Consultant (self-employed)

Dais

Business Intelligence Consultant / Data Engineer

ING Bank Plc.

Data Engineer & BI/DWH Consultant

Ordina

MS BI Developer

BI4U Ltd.

Product Consultant

BWise Ltd.

Sybase Developer

ING Bank Plc.

Graduation Intern

WilroffReitsma Ltd.

Intern

ABB Benelux Plc.

Sr Data Engineer

Boston Consulting Group

Regulatory Reporting Specialist

ING Bank Plc.

Data Warehouse Specialist / Project Manager

ING Domestic Retail Bank Plc.

BI / SQL / CRM Specialist / Data Mining & Analytics Consultant

ING Domestic Retail Bank Plc., Customer Intelligence Department

BI / SQL / CRM Specialist / Data Mining & Analytics Consultant

ING Domestic Retail Bank, Customer Intelligence Department

Sr BI Developer

KASBANK Plc.

Sr Data Engineer

Meta Platforms Inc. (Facebook)

Sr MSBI Developer / Data Analyst / DWH Modeler

NIBC NV

Sr Data Engineer

Newsela Inc.

Data Engineer / Marketing Software Integration Specialist

Rabobank Corp.

Sr Data Engineer

Randstad Technologies

Open Source DWH Designer and Developer

SPIL Games LLC

Team Lead BI

Simon Loos Ltd.

Senior Software Developer Sybase

Stater Plc.

Senior Microsoft BI Developer

Telenet Plc.

Data Warehouse Developer & Test Specialist

UWV

Sr MS Developer

Volkswagen Pon Financial Services

Software Engineer SQL

WSW

Sr Data Engineer

WarnerMedia (HBO)

Data Analyst / Audit & Financial Data Validation and Test Specialist / SQL Server and SSIS Developer

WestlandUtrecht Bank Plc.

Marketing Intelligence Specialist

Wolters Kluwer Plc.

Summary

Languages

Education

Open Universiteit

MSc in Business Process Management & IT (minor: Data Science & Analytics) · Business Process Management & IT · Amsterdam, Netherlands

University of Amsterdam Business School

Pre-Master of Science in Business Studies · Business Studies · Amsterdam, Netherlands

Hogeschool Inholland

Bachelor of Applied Science in Business Informatics · Business Informatics · Diemen, Netherlands

Certifications & licenses

SQL And Python Developer

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