Design and lead implementation of system changes that deliver high performance, scalability and observability for displaying and tracking ads worldwide. Develop tools and optimizations to drive measurable improvements in critical user performance metrics.
Implement and maintain high-quality frontend and full-stack solutions for displaying Ads globally, focusing on extreme performance and scalability.
Develop monitoring systems (RUM and Synthetic) to track crucial metrics like reliability or viewability and use data to diagnose and resolve performance bottlenecks.
Collaborate closely with Ads Layouts specialists and backend engineers to ensure smooth data flow and optimal architectural alignment for performance-critical features.
Write, test, and deploy robust, efficient, and well-documented code in JavaScript/TypeScript/Python/Java, ensuring adherence to the highest coding and performance standards.
Provide hands-on technical leadership: solving complex system challenges, participating in planning and scoping of projects, and ensuring the implementation of the highest coding standards through participation in code reviews.

8+ years of hands-on experience in software engineering, including the understanding of Frontend Development and its internal mechanisms.
Practical experience and strong understanding of Web Performance optimization techniques and advanced loading strategies (caching, asset delivery).
Solid proficiency in JavaScript/TypeScript and modern frameworks like e.g., React. Experience with relevant build tooling (e.g., Webpack, Vite).
Very good knowledge of fundamental Internet protocols and technologies (DNS, HTTP, cookies and others).
Practical ability to observe, monitor and analyse the operation of production systems (and draw valuable conclusions from it).
Good understanding of full-stack concepts, including working with backend APIs (Node.js, Python, or Java) and deployment/CI/CD pipelines.
C1 level in English and Polish.

Projects focused on extreme performance and high code quality – solid code reviews are our standard.
Collaboration within an interdisciplinary, self-sufficient team (including DevOps, database experts, backend developers, product designers, and QA engineers).
Hardware and software tailored to your preferences (e.g., MacBook, AI tool licenses).
Flexible working conditions – no core hours, fully remote cooperation possible.

Senior Full Stack/Web Performance Engineer

Key skills