Big Data Engineer IV at OpenX

At OpenX, we are dedicated to unlocking the full economic potential of digital media companies. We achieve this by building advanced advertising markets and technologies designed to provide optimal value to publishers and advertisers across every screen. Our team is uniquely experienced in designing and operating high-scale ad marketplaces, and we are currently looking for creative, thoughtful executors who are passionate about applying technical innovation and operational excellence to the frontiers of digital advertising.

We operate at a massive scale, utilizing a 100% cloud-based platform on GCP. Our systems handle over 400 billion ad requests every day, supported by 120,000 CPUs and 140 TB of RAM daily. With over 50 PB of data processed each week and more than 1,200 production deployments every month, you will be working at the cutting edge of data engineering. You will join our core data development team to architect and deliver new features, ensuring scalability, performance, and reliability in every line of code you write.

Key outcomes

• Design and implement large-scale data processing systems.
• Collaborate with product teams to define requirements and take full ownership of projects from inception to completion.
• Analyze and enhance the efficiency, stability, and scalability of our applications.
• Adopt a long-term mindset to solve problems permanently rather than applying temporary fixes.
• Identify and eliminate unnecessary complexity within our systems.

Requirements

• At least 8 years of professional experience in Java, Scala, or Python development.
• Minimum of 3 years of experience in developing Big Data systems.
• Proven ability to build complex data pipelines using SQL and transformation tools like dbt or Dataform.
• Expertise in BigQuery or similar data warehouses, including performance tuning and monitoring.
• Strong understanding of data orchestration tools like Airflow, including the ability to troubleshoot and extend pipelines.
• Cloud experience with GCP or AWS, along with proficiency in Kubernetes and Docker.
• Solid grasp of CI/CD, automated testing, and DevOps practices.
• A deep understanding of algorithms, data structures, and database system design, including RDBMS or NoSQL.
• A bachelor’s degree in computer science, physics, or a related field.
• Fluency in both English and Polish.

Preferred qualifications

• A master’s degree in a relevant field.
• Experience working within SCRUM or Agile environments.
• Prior experience in advertising technology, marketing technology, or digital media.
• A proactive, self-starting attitude with the ability to independently identify areas for improvement.
• Strong communication skills and a collaborative, team-oriented mindset.

Compensation

We offer competitive compensation packages, including an employment contract with a salary range of 22,100 to 26,000 PLN gross per month, or a B2B arrangement at 180 to 207 PLN net per hour. Benefits for employees on contract include an annual performance bonus, private health care for you and your family, life and travel insurance, a pension scheme, and a holiday allowance. You will also enjoy flexible working hours, remote work options, a monthly work-from-home allowance, and access to professional development resources like LinkedIn Learning and tech workshops.

How to apply

If you are interested in joining our team and tackling challenges at scale, we invite you to apply for this position. Please note that all interview stages are conducted remotely. We look forward to reviewing your application.