Senior Fullstack Engineer – React and Kotlin Specialists

Our client is a leader in building advanced advertising tools, focusing on creating intelligent recommendation systems and automating campaign management for advertisers on Allegro Ads.

• At least 3 years of experience in full-stack development, with a focus on React and Kotlin.
• Strong proficiency in TypeScript, React, HTML/CSS, and backend technologies like Kotlin, Spring Boot, and microservices.
• Experience working with cloud ecosystems, preferably GCP.
• Solid understanding of database management, including MongoDB and SQL.
• Familiarity with event-driven architectures and large-scale data processing.
• Ability to communicate effectively in Polish and English.
• Experience working in an Agile environment with a focus on delivering high-quality software.

Nice to have:

• Certifications related to GCP or microservices architecture.
• Experience with agentic coding tools like Copilot/OpenCode.
• Knowledge of accessibility standards (a11y) and performance optimization techniques.

• Develop and maintain backend services using Kotlin, integrating machine learning-driven recommendation engines in collaboration with data science teams.
• Build scalable, event-driven architectures to process large data volumes within cloud environments, leveraging GCP.
• Design and implement high-performance APIs to support analytical dashboards and market benchmarks.
• Create and optimize scalable microfrontends using React, prioritizing accessibility and server-side rendering for analytical tools.
• Collaborate with cross-functional teams to deliver seamless, secure, and efficient software solutions.
• Ensure high code quality through testing frameworks such as Jest, Vitest, or Playwright, with a focus on performance and reliability.
• Contribute to evolving microservice architectures, utilizing Spring Boot, MongoDB, SQL, and cloud-native tools.
• Participate actively in code reviews, sprint planning, and technical discussions to foster continuous improvement.

Only candidates with an existing legal right to work in the European Union will be considered for this role.