Senior Quality Engineer (Data)

Description

Join the Data Engineering team as a Senior Quality Engineer (Data) to ensure the quality, reliability, and integrity of data platforms and products. You will design and maintain automated data quality checks, lead root-cause analysis for complex quality issues, and champion quality across the software development lifecycle. The role includes validating ETL/ELT processes on Databricks/Spark and driving test automation through the GitLab CI/CD pipeline.

Responsibilities

• Design, develop, and maintain automated data quality checks across the Medallion architecture (Bronze/Silver/Gold) using dbt tests, Great Expectations (or equivalent), and custom PySpark assertions
• Investigate complex quality issues, perform root cause analysis, and drive preventative actions
• Work with Data Engineers, Data Designers, Product Owners, and stakeholders to define quality requirements, identify risks, and implement QA strategies
• Contribute to Agile ceremonies and promote quality engineering best practices throughout development
• Create and maintain test documentation (test strategies, test plans, test cases, execution and closure reports)
• Validate ETL/ELT processes on Databricks and Apache Spark, including Delta Lake integrity, schema evolution handling, and job performance regression
• Own Unity Catalog-level data governance checks (lineage, access control validation, table certification status) for QA sign-off
• Champion test automation in the GitLab CI/CD pipeline, including contract testing with Pact/PactFlow where applicable and automated DoD validation gates before production
• Stay up to date with modern Quality Engineering and testing practices; mentor other team members
• Support the QE-to-Data-Engineering skill uplift path (SQL/dbt/PySpark/Unity Catalog proficiency benchmarks)

Requirements

• Extensive Quality Engineering experience, ideally in Data Engineering or Big Data
• Strong understanding of quality engineering principles, test strategy, test automation, and QA best practices
• Advanced SQL, including writing and interpreting dbt models and dbt tests
• Python and PySpark proficiency to build test harnesses and data validation/reconciliation checks against Spark DataFrames
• Hands-on Databricks pipeline experience (notebooks, job orchestration, Delta Lake) — strongly preferred
• Experience designing/maintaining automated test frameworks and integrating them into CI/CD
• Good understanding of cloud-based data platforms and modern software development practices
• Experience in Agile teams and collaborating effectively with cross-functional engineering and product teams
• Analytical and problem-solving skills for investigating complex quality issues and identifying root causes
• Excellent communication and stakeholder management skills
• Proactive mindset, strong attention to detail, and passion for delivering high-quality data solutions
• Excellent English (written and spoken)

Benefits

• Salary: 19,000–26,000 PLN gross per month on an employment contract
• Private medical healthcare at LUXMED (including dental care)
• Medicover sports card (Fit&More package)
• Employer-paid life insurance
• 30-minute lunch break included in the 8-hour working day
• Training & Buddy program, wellbeing program
• Co-financing of monthly public transport tickets in Kraków
• Comfortable office environment with the possibility of home office
• Language courses, accounting courses, access to LinkedIn Learning, and support for studies and certifications