Data Platform Tester

We are looking for you if you want to work at one of Hungary's leading telecommunications companies to help our clients navigate the digital world. Take the first step, bring your inspiring ideas and join our supportive and creative Data team.

Be curious and responsible, work passionately and be open to development. Let’s reach our goals together, because at Yettel you can inspire true change while being yourself. Who are we? More than 1,800 colleagues working at nearly 130 locations across the country forming one big team and enjoying an unlimited experience. We have a lime heart and Yettel enables us to make our dreams come true.

Join Yettel Hungary as

Data Platform Tester,

be yourself and make a difference in the world.

The tester ensures that all components of the data platform—data ingestion, processing, storage, and consumption—work as expected and meet quality standards. The tester validates data integrity, system functionality, and compliance with business requirements. In addition, he/she will work closely with data engineers, developers, and business analysts to validate data pipelines, integrations, and reporting systems.

You will have the following responsibilities:

• Data Validation & Quality Checks
  • Verify data accuracy, completeness, and consistency across sources.
  • Check for duplicates, missing values, and schema mismatches.
  • Validate transformations and aggregations against business logic.
  • Create tools to detect and validate source schema changes.
• ETL/ELT Testing
  • Test data pipelines for correct extraction, transformation, and loading.
  • Ensure jobs run within expected timeframes, handle edge cases.
  • Maintain the required logging and alerting workflows.
• Integration Testing
  • Validate integration between different components (e.g., ingestion tools, data lake ETL processes, source DBs, APIs).
  • Test compatibility with upstream and downstream systems.
• Performance & Scalability Testing
  • Assess query performance and pipeline throughput.
  • Simulate large data volumes to ensure the platform scales properly.
• IaC & Automation
  • Develop automated DQ rules and test scripts for recurring checks (e.g., schema validation, data profiling).
  • Use frameworks like pytest, Python Deequ or AWS Glue Data Quality for data quality.
  • Create the required IaC test modules and ensure they are integrated and deployed with CI/CD pipelines 
• Security & Compliance Testing
  • Validate data access controls, encryption, and compliance with GDPR or other regulations.
• Regression Testing
  • Ensure new changes do not break existing functionality.
• Reporting & Documentation
  • Document test cases, results, and defects.
  • Communicate findings to developers, data engineers, and stakeholders.

You are the ideal candidate for our team if you have / are:

• Data validation: solid SQL knowhow
• Automation and scripting: Python, Pyspark
• Data Quality Tools: Deequ, AWS Glue data quality, great expectations. 
• ETL Tools: Airflow, optionally dbt
• Cloud Platforms: AWS
• Testing Frameworks: pytest
• Version control and CI/CD pipelines: Solid Git knowhow and preferably experience with GitLab pipelines 
• Familiarity with data governance, security, and compliance standards is a plus.

Discover the opportunities offered by Yettel.

#FlexibleWorking: On Tuesdays, Wednesdays and Thursdays we work in the nature-friendly and innovative Yettel House, and in the Garden office in the summer. On Mondays, if our projects or tasks require it, we have the opportunity to work in the Yettel House, but also from home, on Fridays we are all in home office.

#Health: We provide our colleagues with collective life and health insurance, paternity leave, and free advice in the areas of lifestyle, psychology, law and finance. Our office gym and saunas also await our employees.

#Technology: It is natural that you will receive a company smartphone with unlimited internet, and we even offer discounted rates for your family and friends.

#Learning: Trainings, courses and an online platform are also available so that you never stop developing! Our goal is to support you throughout your personal and professional career, while you are constantly learning new things!

#YettelHQ: Our headquarter at Törökbálint is one of the most modern office buildings in the country, with a panoramic terrace, an outdoor sports field and an alternative garden office.

#YettelBus: You can also get to Törökbálint with Yettel's buses, which are available to everyone. You don’t need to show any documents when boarding. These buses leave from several stations in the city: Népliget, Kelenföld, as well as Déli pályaudvar stations, and you can recognize them by the "Yettel bus - Yettel" sign on the front of the vehicles.

Are you interested?

Please submit your application and we’ll contact you soon. For more information about the application process please visit our career page. Until then, please follow us for the best Yettel moments on Instagram and LinkedIn.