Ozan Şen

• I am working on a hourly rate as freelance backend python developer to assist a company in data analytics, data quality, data validation, data transformation, testing (class-based and functional) using Python 3.9+.

• Designed and maintained data pipelines using ssis, integrating data from diverse sources (oracle db, flat files, excel, xml, json, api, sftp) into the DWH. • Built and optimized workflows, managed job schedules(ssms), and debugged failures to ensure reliable daily data loads. • Developed advanced sql server logic: stored procedures, triggers for data integration. • Created and deployed SSRS reports( Report Server), managed report permissions, and trained business users on access and usage.

• Led full-cycle ETL and data warehouse projects for various clients, focusing on analytics, data validation (Pydantic, dataClasses), Testing(Pytest), API Design (FastAPI), and performance optimization. • Performed data validation, solid principles, data modeling, data quality, type checking and code testing scripts using python 3.11+. • Designed scalable ETL packages and orchestrated jobs using sql, python, and pandas. • Developed ETL automation using python and pandas for high-volume datasets.