Polina Stelmakh

Senior Data Engineer

Migrating the corporate data warehouse from Oracle to a Trino + Iceberg Lakehouse architecture, rebuilding transformation logic as dbt models on the new platform. Implementing DataHub as the company-wide data catalog: configuring ingestion recipes for Oracle, PostgreSQL, dbt, and Airflow sources to establish end-to-end column-level lineage across the DWH. Maintaining and developing the existing DWH: writing Airflow DAGs that load data from source systems through staging into fact and dimension tables. Building dbt models for transformation logic, tests, and documentation. Writing technical documentation for data pipelines, dbt models, and DWH objects to support knowledge sharing across data and analytics teams. Collaborating with data analysts, business analysts, and cross-functional teams to define requirements and deliver data solutions.

Data Engineer

Deploying and configuring data catalogs (DataHub, OpenMetadata). Writing and optimizing ETL scripts, DAGs for data pipelines, and process automation (including ETL in Pentaho). Reporting and dashboard creation in QlikSense and Apache Superset (scripts, data visualization). Database migration and integration of Change Data Capture (CDC) systems. Optimizing and automating mailing processes. Parsing and processing data from multiple websites. Creating, optimizing, and maintaining datamarts. Server monitoring in Grafana. Creating and managing Kafka consumers for efficient data processing. Collaborating with data analysts, business analysts, and cross-functional teams to define requirements and deliver data solutions. Mentored two interns: onboarding, task reviews, and technical guidance.

• reduced sending time by 20

Data Engineer Intern

Parsed XML and Excel data into tables. Took part in creating Data Warehouse (created transformations to do manipulations with data). Built some pipelines for various data manipulations. Created hubs and satellites. Created high-loaded tables on different servers. Made various queries regarding the consistency and safety of data. Applied and integrated ACID principles. Made and optimized a workflow in Knime to provide a JSON dataset for API. Coded and built a heat map API with usage of D3.js, using dataset acquired from side API requests. Deployed API by using Node.js, JS and Docker.