Walter Stepanov
Data Architect
San Diego,CA
Summary
Data Architect with 18+ years of experience designing and implementing enterprise-scale data solutions across Fortune 500 companies. Specialist in Neo4j knowledge graphs, Snowflake data platforms, and Python-driven ETL/ELT pipelines. Proven ability to build scalable lake house models, semantic frameworks, and enterprise knowledge graphs supporting analytics, AI/ML, and business intelligence. Adept at enabling fraud detection, customer 360, and underwriting intelligence through graph-based modeling. Skilled communicator and mentor with a track record of delivering resilient, governed, and cost-efficient data platforms.
Results-driven data engineering professional with solid foundation in designing and maintaining scalable data systems. Expertise in developing efficient ETL processes and ensuring data accuracy, contributing to impactful business insights. Known for strong collaborative skills and ability to adapt to dynamic project requirements, delivering reliable and timely solutions.
Overview
26
26
years of professional experience
2
2
Certifications
Work History
Staff Data Engineer
Qualcomm
05.2024 - 10.2025
- Architected qPanDa Knowledge Base, a scalable AI-powered engineering knowledge graph using Neo4j and Weaviate.
- Unified Neo4j, PostgreSQL, Snowflake, Athena, Oracle, and SQL Server into a hybrid architecture supporting graph traversal, vector search, and relational metadata.
- Designed semantic data models and dimensional schemas tailored to Power BI and enterprise analytics.
- Built Python + Snowflake ETL/ELT pipelines in Databricks, optimizing query performance and semantic cohesion.
- Invented strategies for dynamic metadata enrichment over immutable Athena/S3 datasets.
- Implemented lineage tracking, governance workflows, and onboarding documentation in Confluence.
- Partnered with AI/ML teams to optimize ingestion pipelines for model training and semantic enrichment.
Senior Database Engineer
Sony Network Entertainment
San Diego, CA
09.2012 - 03.2024
- Modernized PlayStation’s global data infrastructure (120M+ users).
- Migrated services from Oracle to DynamoDB/PostgreSQL, enabling scalable, low-latency access.
- Designed pragmatic schemas and semantic layers for Power BI dashboards.
- Backfilled and reconciled global customer master data for consistency across policy/claims ecosystems.
- Instrumented production systems with Splunk/Datadog for observability and resilience.
- Mentored engineers on cloud migration, performance tuning, and governance best practices.
Lead Oracle Consultant
Wells Fargo Bank
07.2011 - 09.2012
- Led conversion of Sybase → Oracle for Secondary Marketing System supporting loan pooling/delivery.
- Implemented governance, security, and performance tuning for critical banking workflows.
- Reduced archive/unarchive processing from 8 hours to 10 minutes; optimized eligibility reporting.
- Mentored engineers in database development and governance protocols.
Senior Oracle DBA/Developer
01.2000 - 01.2011
- Senior Oracle DBA/Developer at Keefe, Bruyette & Woods, Credit Suisse, Bank of America, Bank of New York Mellon, Goldman Sachs, Cendant Mortgage, Qwest Consulting, JW Seligman, Mizuho Bank, Sony Music Entertainment.
- Designed and optimized data warehouses, semantic models, and reporting systems.
- Delivered fraud detection, compliance, and customer intelligence solutions in financial services.
- Extensive experience with Oracle, Sybase, DB2, PowerBuilder, PL/SQL, ETL automation.
Education
M.D. - Economics, Minor: Information Systems/Computer Technology
State University
St. Petersburg, RussiaM.S. - English & Literature
Skills
- Graph & Semantic Modeling: Neo4j, Weaviate, ontology frameworks, enterprise knowledge graphs
- Cloud Data Platforms: Snowflake, AWS (EC2, S3, Athena), hybrid architectures
- Programming & Pipelines: Python, PySpark, Databricks, SQL (Oracle, PostgreSQL, SQL Server), ETL/ELT optimization
- Data Modeling: Logical/physical schemas, dimensional/star/snowflake schemas
- Governance & Metadata: Data quality, lineage tracking, cataloging, reproducibility
- Domain Expertise: Insurance (policy, claims, underwriting, fraud detection, customer master data)
Certification
AWS Running Containers – 2023-11
Timeline
Staff Data Engineer
Qualcomm
05.2024 - 10.2025
Senior Database Engineer
Sony Network Entertainment
09.2012 - 03.2024
Lead Oracle Consultant
Wells Fargo Bank
07.2011 - 09.2012
Senior Oracle DBA/Developer
01.2000 - 01.2011
M.S. - English & Literature
M.D. - Economics, Minor: Information Systems/Computer Technology
State University