Senior Data Migration Engineer (f/m/x)

We are looking for a Senior Data Migration Engineer to join Sii and our delivery team focused on SQL Server to Snowflake migrations for a global client operating in the tobacco industry. You will contribute to the development of Matillion pipelines, AI-assisted code conversion, automated testing, and data reconciliation from the outset.

Your tasks

• Migrating database objects such as stored procedures, views, functions, and ETL logic from Microsoft SQL Server to Snowflake while ensuring functional equivalence
• Designing, developing, and optimizing Matillion ELT pipelines for loading and transforming data into Snowflake
• Building automated data validation and reconciliation frameworks in Python to compare source and target datasets during migration
• Analyzing and resolving data discrepancies related to data type conversions, SQL dialect differences, and transformation logic
• Leveraging AI coding assistants to accelerate code conversion and refactoring, while reviewing and productionizing AI-generated code
• Optimizing Snowflake performance by tuning queries, virtual warehouses, clustering strategies, and transformation workloads
• Creating automated testing suites to validate migration results and prevent regressions throughout the delivery lifecycle
• Implementing CI/CD processes using Git and deployment pipelines to manage database, Snowflake, and Matillion releases across environments
• RequirementsAt least 5 years of hands-on experience developing and maintaining enterprise data warehouse solutions
• Strong expertise in Microsoft SQL Server (T-SQL) and Snowflake, including performance optimization, stored procedures, views, functions, and query tuning
• Proven experience migrating SQL Server workloads to Snowflake or another cloud data warehouse
• Hands-on commercial experience with Snowflake, including knowledge of its architecture and performance optimization techniques
• Strong Python skills for data engineering, with practical experience using pandas and pytest for automated testing and data validation
• Experience using AI coding assistants in professional software development, with the ability to review and productionize AI-generated code
• Advanced level of English
• Nice-to-have requirements
• Experience with Matillion ETL and building production ELT pipelines
• Knowledge of traditional data warehousing concepts and exposure to cloud/data platforms such as AWS or AzureA genuine willingness to learn, experiment, and troubleshoot, with comfort working through ambiguity and iterating on AI output
• Advanced level of Polish