Recommended expert

Alexander Zhirov

Senior Data Architect & Data Engineer

Alexander Zhirov
Berlin, Germany

Experience

Sep 2022 - Jan 2025
2 years 5 months

Senior Data Solutions Engineer

VMware Inc.

  • Architected and deployed private cloud data platform on VMware vSphere, integrating Greenplum MPP, Apache Kafka, Kubernetes, and Apache Solr, and developed real-time ingestion pipelines with Kafka Connect and Schema Registry.
  • Led Oracle Exadata to Greenplum migration, rearchitected data models, optimized storage, implemented RabbitMQ with Debezium for CDC, and deployed VectorDB for Generative AI.
  • Designed and executed multi-cloud migration PoC across AWS, Azure, and GCP, defined KPIs for throughput, latency, and cost efficiency, executed bulk data transfers, validated analytics and streaming workloads, and delivered full-scale architecture recommendations.
  • Assessed legacy on-premises infrastructure and designed modern cloud-native data platforms using Greenplum and containerized microservices, advising on scalability, disaster recovery, and high-availability.
Feb 2021 - Present
5 years

Senior Solution Architect - Data and Analytics

HCL Technologies Inc.

  • Led AWS data platform modernization by architecting and developing centralized medallion data architecture with dimensional model and integrated data marts using Airflow and dbt.
  • Created data lineage for Tableau and Salesforce CRM to improve auditability and root-cause analysis and optimized Snowflake using clustering keys, result caching, and compute resource allocation.
  • Migrated large Oracle data warehouse to AWS using Amazon Redshift and Informatica Cloud Data Integration, designed cloud-native data model and architecture, integrated AWS S3 and Lambda, implemented multi-region multi-cluster data sharing, and set up SageMaker for ML/AI.
  • Architected Azure BI platform on Azure Databricks and PowerBI, implemented streaming pipelines using Debezium and Delta Live Tables, developed semantic tabular model using Azure Analysis Service, and optimized Spark cluster performance.
  • Enhanced Data Vault model by tuning SQL queries, implementing materialized views, optimizing keys and hashing, and developing Point-in-Time and Bridge tables.
  • Migrated IBM InfoSphere MDM to Informatica Cloud Pak for Data, developed data mapping, transformation, and validation processes, and performed containerized environment benchmarking.
  • Conducted technical assessments, developed cloud transformation roadmaps, delivered executive presentations and workshops, and collaborated in complex program management.
Aug 2020 - Feb 2021
7 months

Lead Data Architect

AUTO1 Group

  • Architected and implemented AWS data warehouse, integrated real-time streaming with Apache Kafka and AWS Aurora.
  • Designed and implemented ETL pipelines using AWS Glue, Spark, and PySpark.
  • Created data lake and data warehouse using Amazon Redshift/Spectrum and S3.
  • Developed master data management and data dictionary with AWS Glue Catalog.
  • Implemented data governance policies, security protocols, and access controls.
Jul 2019 - Aug 2020
1 year 2 months

Associate VP - Data Solutions and Analytics

Evalueserve Inc.

  • Led modernization of on-premises legacy data platform to cloud-native AWS architecture with high-volume fault-tolerant ETL pipelines using AWS Glue, Lambda, Kinesis, and S3, partitioned data lake architecture, and integrated Redshift and Athena.
  • Designed data monetization architecture for telecom external data sharing, implemented ingestion and transformation with AWS Glue, EMR, and S3, applied anonymization, tokenization, and differential privacy for GDPR compliance, and developed segmentation frameworks.
  • Architected enterprise data warehouse consolidating transactional, operational, and third-party sources with ETL/ELT using Azure Data Factory, Python, and SQL, and optimized Snowflake storage and performance.
  • Architected IoT analytics platform in AWS with Kafka ingestion, Spark transformation with gap-filling techniques, and rule-based predictive models in Python and SQL.
  • Established data governance processes for GDPR, CCPA, and ISO 27001 compliance including classification, lineage, cataloging, and retention policies, and led cloud migration assessments across AWS, Azure, and GCP.
  • Provided strategic guidance to C-level leaders, delivered workshops and briefings, and led cross-functional teams.
Apr 2017 - Jul 2019
2 years 4 months

Lead Data Architect and Data Engineer

Siemens Energy

  • Led migration of 40PB of data from Hadoop HDFS to AWS EMR, S3, Redshift, and Snowflake with zero-downtime and performance optimization.
  • Implemented cloud data lake with automated ETL pipelines using AWS Glue, Spark, and Lambda.
  • Developed real-time data pipelines for structured and unstructured data.
  • Optimized Redshift and Snowflake performance using WLM and advanced query optimization.
  • Provided technical leadership to cross-functional teams and collaborated with global teams in US and India.
Dec 2016 - Apr 2017
5 months

Senior Data Warehouse Architect

Esty Inc.

  • Designed and implemented scalable data warehouse and self-service BI platform supporting analytics and reporting.
  • Led ETL development and dimensional modeling using PostgreSQL and Talend to automate data ingestion and transformation.
  • Optimized database schema and indexing to improve query performance and BI report generation time.
  • Developed and automated data quality and validation workflows.
Sep 2015 - Dec 2016
1 year 4 months

Data Engineering Team Manager

Nexon Europe Inc.

  • Led data engineering and infrastructure projects delivering centralized data warehouse and BI platform.
  • Consolidated databases and executed secure migrations to partner data centers.
  • Implemented technical standards and deployed cloud-based backup and disaster recovery on Amazon S3/Glacier.
Oct 2013 - Sep 2015
2 years

Lead DBA and Senior Systems Engineer

Aeria Games GmbH

  • Managed over 100 high-transaction Oracle, MSSQL, and PostgreSQL databases for online gaming, optimizing performance and backups.
  • Integrated AWS RDS to reduce costs and improve query speeds.
  • Developed BI solutions on Redshift and Tableau.
  • Ensured high availability with PostgreSQL clustering and SQL Server virtualization.
Apr 2012 - Oct 2013
1 year 7 months

Senior DBA and Database Architect

William Hill Plc.

  • Led high-availability OLAP/OLTP database operations for real-time betting.
  • Migrated core systems to SQL Server 2008 and reengineered ETL workflows.
  • Implemented real-time replication, automated backup and recovery, and enforced GDPR/PCI-DSS compliance.
  • Optimized mission-critical systems for availability and performance.
Mar 2011 - Apr 2012
1 year 2 months

Technical Project Lead and Oracle Expert

Zimory GmbH

  • Supported development of IaaS cloud management software by designing robust database architectures and cross-platform replication with Oracle Streams and LogMiner.
  • Automated deployments and optimized performance and scalability.
  • Provided technical demos and architecture consultations to support sales.
Apr 2006 - Mar 2011
5 years

Lead Oracle DBA and Systems Engineer

Vodafone Group Plc.

  • Managed 24/7 mission-critical Oracle databases with RAC, ASM, Data Guard, and workload optimization.
  • Consolidated databases, automated data integration and backups, and enforced SOX compliance.
  • Provided technical leadership to DBA teams.
May 2003 - Apr 2006
3 years

Senior Oracle DBA and Subject Matter Expert

Amdocs Inc.

  • Led mission-critical Oracle database operations supporting telecom billing systems, achieving 99.99% uptime through performance tuning and disaster recovery.
  • Enhanced data processing with PL/SQL and ETL workflows and improved query performance.
Jun 2000 - May 2003
3 years

Oracle DBA

ACS Ltd

  • Managed enterprise Oracle databases with a focus on high availability, performance, and security.
  • Performed seamless migrations and implemented robust backup and recovery strategies.

Summary

  • Senior Data Architect and Data Engineer with over 25 years of experience in designing and delivering large-scale data architectures and strategies, analytics solutions, cloud transformations and migrations.
  • Extensive hands-on experience in architecting and implementing large-scale data platforms in cloud and on-premises.
  • Strong proficiency in data architecture: Data Warehouse, Operational Data Store, Data Lake, Lakehouse, Data Mesh.
  • Deep expertise in data modelling: Relational, Dimensional (Star, Snowflake, Galaxy), Data Vault, Data Marts, 3NF.
  • Extensive experience with Massively Parallel Processing (MPP) and Distributed Data systems.
  • Significant knowledge and experience with Data-as-a-Service (SaaS/DaaS), AI/ML analytics and Business Intelligence.
  • High Proficiency in designing and implementing high-performance ETL/ELT and streaming data pipelines.
  • Strong background in Data Governance, Data Lineage, Data Quality and Data Security.
  • Expert in optimization and administration of high volume OLTP/OLAP databases in mission-critical 24x7 environments, improving performance, scalability, and high availability.

Skills

Technical

  • Relational Databases: Oracle, Postgresql, Ms Sql Server, Mysql, Aws Aurora/rds
  • Data Warehousing: Snowflake, Aws Redshift, Azure Synapse, Exadata, Teradata, Greenplum
  • Big Data: Spark, Hadoop (Hdfs, Hive), Aws Emr, Aws S3, Azure Adls
  • Data Integration & Streaming: Pentaho, Talend, Airflow, Dbt, Kafka, Kinesis, Rabbitmq, Aws Glue, Matillion
  • Cloud & Infrastructure: Aws, Azure, Vmware Vsphere, Kubernetes
  • Programming & Scripting: Python, Pyspark, Java, Powershell, Perl, Unix Shell
  • Operating Systems: Unix (Hp-ux, Solaris, Aix), Linux (Rhel, Debian/ubuntu), Windows Server
  • Devops & Methodologies: Ci/cd Pipelines, Agile/scrum Practices

Personal

  • Problem-solving & Analytical Thinking - Strong Ability To Troubleshoot Complex Data And Infrastructure Issues Efficiently.
  • Customer-focused Approach - Service-oriented Mindset With Experience In Client-facing Roles.
  • Quick Learner & Adaptability - Rapidly Adapts To New Technologies, Tools, And Business Domains.
  • Independent & Proactive - Self-motivated With A Strong Ability To Work Autonomously.
  • Team Collaboration & Leadership - Effective Team Player With Experience Leading Cross-functional Teams And Mentoring Colleagues.
  • Strong Communication Skills - Clear And Concise In Technical And Non-technical Discussions.

Languages

German
Advanced
English
Advanced

Education

Oct 2006 - Jun 2010

University of Hertfordshire

Bachelor of Science, Computer Science · Computer Science · Hatfield, United Kingdom

Oct 1997 - Jun 2000

Technological College of Beer-Sheva

Engineer, Software Engineering · Software Engineering · Be'er Sheva, Israel

Certifications & licenses

Microsoft SQL Server 2012 Administrator (MOC 10775)

TÜV Rheinland Group

Oracle Certified Professional (OCP)

Oracle University

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