Aristeidis Kesopoulos

• Migrated a legacy VPS-hosted real-estate platform to AWS Lightsail and S3, reducing annual infrastructure costs by ~5× and improving backup reliability with automated snapshot workflows and IAM-based access controls • Designed and deployed a serverless ETL using S3, Glue, Lambda, Step Functions, and Athena, reducing data latency from several hours to under 10 minutes through retries, schema validation, and alerting • Built a reproducible analytics environment with Meltano, dbt, DuckDB, and Superset, enabling self-service reporting through version-controlled transformations, dbt tests, and Git-based CI/CD

• Built and deployed end-to-end ELT pipelines in the company’s Snowflake data warehouse, integrating Lightspeed POS data across 15+ hospitality business units using Airbyte, dbt, and Metabase • Delivered the Lightspeed integration one month ahead of schedule, enabling a unified self-service dashboard for restaurant managers and a senior stakeholder, consolidating previously siloed revenue and operational metrics • Designed a complete dbt transformation layer (raw → intermediate → marts) with documentation and tests, improving transparency and reliability of reporting for gastronomy operations • Developed a second ELT workflow for Zendesk customer-feedback data, automating manual analysis and providing management with a unified view of customer sentiment • Identified upstream data-quality issues in Lightspeed (categorization inconsistencies) and flagged them to leadership, helping establish a more reliable workflow and improving trust in core operational data

• Developed Python ETL workflows to extract and integrate property data from external listing APIs into the company's MySQL database, expanding dataset coverage and reducing manual data-entry workload by 30-40% • Implemented data validation logic to detect price anomalies and missing required fields, improving data accuracy for customer-facing search • Optimized database query performance through indexing and query refactoring, reducing report generation time and enabling faster access to inventory and pricing data • Built automated reporting workflows using Python to generate weekly market and internal operations analysis, replacing manual Excel-based analysis and enabling faster business decisions