Full-Stack Software Engineer (React & Kotlin)

About the Position

We're looking for a Full-Stack Software Engineer (React & Kotlin) to join our high-scale, PPC advertising platform in the e-commerce sector. You will work on ML-driven recommendation engines, high-volume event data pipelines, and real-time merchant analytics dashboards.

Responsibilities

• Design, build, and maintain scalable React-based microfrontends for analytics dashboards and merchant tools with a focus on Accessibility (a11y) and Server-Side Rendering (SSR).
• Build high-performance backend microservices in Kotlin and Spring Boot to power real-time dashboards, benchmarks, and recommendation engines.
• Partner closely with Data Science teams to serve personalized recommendations and automated campaign insights.
• Participate in developing a distributed, event-driven cloud architecture for processing campaign data in real time.
• Maintain high engineering standards through automated testing (unit, integration, E2E via Jest/Vitest/Playwright), code reviews, CI/CD, and DevOps practices.

Requirements

• Frontend Focus: Strong, proven expertise in React, TypeScript, CSS/HTML, state management, and modern testing frameworks (Jest / Vitest / Playwright).
• Backend Proficiency: Solid hands-on experience in Kotlin with Spring Boot, REST APIs, and microservices architecture.
• Commercial experience working with MongoDB, SQL databases, and cloud environments (GCP preferred).
• Familiarity with agentic coding tools and assistants (e.g., GitHub Copilot, OpenCode).
• Proactive, relational, highly engaged, open-minded, and strong communication skills.
• Fluent in English (B2+).

Nice to Have

• Experience with Microfrontends, Server-Side Rendering (SSR), and Accessibility standards (a11y / WCAG).
• Exposure to Scala, Big Data engines (Apache Spark), or search technologies (ElasticSearch).
• Prior background in AdTech, PPC advertising, or large-scale e-commerce systems.

We Offer

• A good and friendly atmosphere in the company and the satisfaction of working with both departmental colleagues and direct superiors.
• Large internal technology conferences, star parties, and team outings.
• Flexible working hours and the option to work remotely or in a hybrid model.
• Clear, straightforward development paths, including managerial or expert paths.
• Facilitation of desired competencies development, subsidized training, and courses.
• Experience in managing national and international projects.
• Free participation in language lessons for those who wish to maintain or develop their language skills.
• Attractively decorated relaxation areas and equipped kitchens with aromatic coffee.
• Support for all passions, including soccer teams, marathon runners, and other active sports.

About the Company

Join a high-scale, PPC advertising platform in the e-commerce sector, built entirely on microservices handling thousands of requests per second. Work on ML-driven recommendation engines, high-volume event data pipelines, and real-time merchant analytics dashboards.

Apply for the Position

Please include the following information when applying:

• First name
• Last name
• Email
• Phone number
• Location
• Experience
• English level
• German level

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