
Konstantinos G.
Analytics Engineer with Analyst Background
Kompetenzen

Meine Dienstleistungen


Portfolio
Arbeitserfahrung
Analytics Engineer
Self Employed • Freiberufler
Nov 2025 - Present • 6 mos
I help businesses and data teams to replace manual Excel reporting and build BI-ready data pipelines and reliable reporting systems. After two years as a data analyst, I transitioned to analytics engineering because I became more interested in the data behind the dashboards and the layer between raw data and the final report. I designed and built a production-style food data lakehouse that solves a real problem. Open Food Facts is a public API with 3M+ product records but zero analyst-ready tables. Nutrichain Open Food Lakehouse is a portfolio project demonstrating my skills in analytics engineering. It turns that raw API into a trusted, queryable lakehouse on Databricks: - Engineered an end-to-end batch ingestion pipeline in Python fetching paginated JSON from the Open Food Facts API, landing raw data into a Bronze Delta Lake table with run-level metadata, hash keys, and audit logging for full lineage traceability - Orchestrated daily pipeline runs using Apache Airflow with task dependencies, retry logic, and Databricks Secrets for API key management — targeting ≥95% job success rate - Transformed Bronze data through a Silver layer using dbt on Databricks: deduplication on business keys, type casting, null handling, and schema validation across 500K+ records from 170+ countries - Modelled a Kimball-style star schema in the Gold layer with dbt (fact_product_nutrition + dim_brand, dim_category, dim_nutriscore, dim_country) connected directly to Power BI via Databricks SQL
Data Analyst
BD • Freiberufler
Jul 2025 - Oct 2025 • 3 mos
Contracted to execute a critical master data integration project following a company acquisition, specifically handling the Greek and French markets: - Tasked with identifying and resolving duplicate customer records between an 8,000-record acquired database and a 514,000-record enterprise database - Engineered custom Excel macros and utilized advanced data functions to automate the matching of customer names, addresses, and IDs across both datasets - Successfully mapped and deduplicated the required records, ensuring a clean migration into the parent company's master database