At OpenX Poland, we are looking for a talented, communicative, and curious Software Development Engineer IV in Test to join our team in Cracow, Poland.
You will join the Core Exchange development team at OpenX. Our exchange handles billions of ad requests every day, connecting thousands of publishers with demand partners across the global advertising ecosystem. The platform runs in the cloud across multiple regions and operates at a scale where performance, reliability, correctness, and every millisecond matter.
You will be part of a cross-functional product engineering team focused on business-critical workflows that support how advertising transactions are configured, reviewed, processed, and validated across OpenX. These tools help users manage business rules, review transaction setup, and keep platform behavior aligned with business agreements and financial processes.
In this senior UI-focused SDET role, you will take strong ownership of test automation for TypeScript-based frontend applications, while also contributing to API integration and end-to-end testing using Python and pytest. This role is well suited for someone who wants to make UI test automation their primary area of expertise while also working regularly in the API testing area. In practice, we expect the work to be roughly two-thirds UI test automation and one-third API testing.
The primary stack for this role includes:
TypeScript, Playwright, React-based applications, Python APIs, Pytest, Spinnaker (CI/CD).
The broader engineering environment also includes Node.js, GraphQL, Java, Go, GCP, and Kubernetes.
You do not need to be an expert in all parts of our backend stack, but you should be comfortable collaborating with backend engineers and understanding service-level behavior.
Prior AdTech experience is helpful, but not required.
Team setup
You will join a cross-functional product engineering team with a dedicated Product Manager, Scrum Master, Engineering Manager, QA engineers, frontend and backend engineers, and regular collaboration with UX designers. This setup gives you direct access to product context and a real opportunity to influence business requirements, solution design, test strategy, and release quality.
On a daily basis, we use the Scrum framework with an open-minded attitude to adapt the process to our needs. Within the team, you will have the opportunity to work closely with other SDETs focusing on different domains, as well as be part of the QA Guild focused on making impactful changes to our tools and processes.
What we offer
- Employment contract (22 595 - 25 254 PLN gross/monthly) OR B2B (181 zł - 202 zł PLN net/hourly)
- Working with the newest technologies such as Cloud Computing (GCP)
- Challenges at work that are difficult to find anywhere else!
- Solving important problems in a scale
- Joining a company that is growing and scaling
- Flexible working hours & remote work option
Key Responsibilities
Design and maintain reliable automated tests across TypeScript-based UI and Python API layers.
Own and evolve test automation for complex frontend user workflows.
Build, maintain, and improve automated UI test suites using Playwright and TypeScript.
Contribute to API integration and end-to-end testing strategy, automation, and coverage using Python and pytest.
Be involved in all phases of product development, from requirements and solution design to validation, deployment, and release readiness.
Partner with software engineers, product managers, and UX designers to identify quality risks early and improve testability.
Apply risk-based testing practices and make pragmatic decisions about test coverage at unit, integration, API, and end-to-end levels.
Improve the reliability, speed, and maintainability of test automation frameworks and CI/CD pipelines.
Investigate test failures, flaky tests, and production issues, and drive root cause analysis with actionable improvements.
Communicate quality risks, trade-offs, and recommendations clearly to engineering and product stakeholders.
Required Qualifications
5+ years of professional experience in test automation or software engineering in test.
Strong hands-on experience with TypeScript and modern frontend test automation frameworks such as Playwright or Cypress.
Ability to design, debug, extend, and maintain test automation frameworks and shared testing utilities.
Strong understanding of modern frontend applications, user workflows, API integration, asynchronous behavior, and common sources of UI test instability.
Experience with API testing and practical experience with Python, preferably with pytest, or strong willingness to work with Python-based API test automation.
Practical knowledge of test design techniques and risk-based testing.
Experience working with CI/CD tools and improving automated test execution in CI environments.
Excellent troubleshooting skills and ability to triage complex issues across application, test, and infrastructure layers.
Experience working in an agile engineering environment.
Strong communication skills and ability to work effectively with SDETs, software engineers, Product, and UX.
Communicative Polish and English.
Desired Characteristics
Experience with Python test automation.
Experience testing React-based applications.
Experience with Google Cloud Platform, Kubernetes, Docker, Spinnaker, or similar cloud and deployment technologies.
Experience with API contract testing, integration testing, or service-level testing.
Familiarity with advertising technology, digital media, or the advertising ecosystem.
Analytical: able to connect business requirements, system behavior, and product risk.
Open-minded: happy to give and receive feedback, not afraid to fail, learn, and move forward.
Proactive: always looking for practical solutions and ways to improve quality and delivery.
Self-organized and self-motivated.
A team player who communicates clearly and helps others raise the engineering quality bar.
If you’re:
We want to talk to you.
Our benefits (on employment contract)
- Annual performance bonus
- Tax-deductible system due to copyright protection: 75%
- Private health care for you and your family (covered by OpenX)
- Private life and travel insurance (Covid insurance included)
- MultiKafeteria program
- Training: access to the LinkedIn learning platform and Tech workshops
- Holiday Allowance
- Pension scheme (PPK from PZU)
- Additional paid day off
- Free parking lot
- Access to peer to peer recognition platform
- Monthly work-from-home allowance and one-time payment when you join us to help you set up your home office
- We celebrate team members' important personal milestones (vouchers, gifts)
