Software Engineer III ( JS/TS)

OpenX is focused on unleashing the full economic potential of digital media companies by making digital advertising markets and technologies designed to deliver optimal value to publishers and advertisers on every ad served across all screens. The company has a team experienced in designing and operating high-scale ad marketplaces, applying market design, technical innovation, operational excellence, and empathetic partner service to digital advertising.

• 4+ years of professional software engineering experience.
• Experience building web applications with JavaScript or TypeScript.
• Hands-on experience with React and modern frontend architecture.
• Solid understanding of component-based development, state management, API integration, and frontend performance.
• Experience designing and developing REST APIs or contributing to backend services, preferably in Python.
• Practical understanding of databases and backend data flows.
• Commitment to software quality, including writing automated tests where appropriate.
• Strong ownership mindset and ability to collaborate effectively with Product, UX, QA, and Engineering.
• Communicative Polish and English languages.

Desired Characteristics:

• Experience with advertising technology, marketing technology, digital media, marketplace platforms, financial workflows, or revenue-related systems.
• Experience with GraphQL.
• Experience with cloud-based systems such as Google Cloud Platform, AWS, or Azure.

• Design and build high-quality, maintainable user interfaces using JavaScript/TypeScript and React.
• Develop and maintain Python-based backend APIs that support frontend workflows and product capabilities.
• Translate business rules, pricing logic, and data dependencies into intuitive user experiences and reliable API integrations.
• Own features end-to-end, from requirements and technical design through implementation, testing, rollout, and operational quality.
• Write and maintain automated tests as part of the development process, including frontend and API-level tests where appropriate.
• Collaborate closely with Product, UX, QA, and Engineering to deliver reliable product experiences for enterprise users.
• Improve the usability, reliability, and maintainability of existing systems.
• Contribute to technical direction, code quality, and engineering practices within the team.

OpenX is committed to equal employment opportunities and does not discriminate against employees or applicants on any legally-recognized basis including age, race, creed, color, religion, national origin, sexual orientation, sex, disability, genetic information, military or veteran status, marital status, gender identity, pregnancy, childbirth or related medical condition, and other protected characteristics as established by law.