Full Stack Developer with Java and React, Analytics Hub

Location: Belgrade, Serbia; Krakow, Poland; Lodz, Poland; Lublin, Poland; Remote.PL, Poland; Warsaw, Poland; Wroclaw, Poland We are looking for a Full Stack Developer with strong experience in Java and React to contribute to the development of an enterprise reporting and analytics platform. You will work on a mature product used by a large global customer base, helping deliver new functionality, improve performance, troubleshoot complex issues, and maintain high quality standards across the application stack. The project focuses on building enterprise grade solutions that provide advanced reporting, data visualization, and analytics capabilities integrated with widely used collaboration and work management platforms. The product serves a large global user base and continues to evolve with new features aimed at improving productivity, decision making, and user experience. Develop and maintain backend functionality using Java, Spring, and REST APIs Enhance and support frontend applications built with React and TypeScript Work with relational databases to implement features, troubleshoot data issues, and optimize query performance Investigate and resolve complex production issues by identifying root causes and implementing long term solutions Collaborate with product, support, and engineering teams to deliver new functionality and product improvements Maintain and extend existing framework based codebases while ensuring stability, performance, and maintainability Create and maintain automated tests to support product quality and reliability Participate in code reviews and contribute to engineering best practices Support CI/CD processes and contribute to code quality and security initiatives Prepare and maintain technical documentation related to features and system behavior 3+ years of relevant full stack work experience Solid backend experience with Java and the Spring ecosystem, including dependency injection and REST controllers; comfortable reading and safely modifying an existing framework based codebase rather than working only on greenfield projects Good command of relational databases and SQL, with the ability to troubleshoot data correctness and query performance issues; experience with multiple database vendors such as PostgreSQL, MySQL, Oracle, and Microsoft SQL Server is a plus Practical experience maintaining production UIs with React (Hooks and component composition) and TypeScript in a strongly typed codebase Familiarity with state management solutions such as Redux, Redux Toolkit, MobX, or similar technologies and modern frontend build tools such as Vite or Webpack Good understanding of object oriented programming principles, common design patterns, and automated testing Highly analytical, with a genuine passion for debugging. Reproducing difficult to replicate issues and identifying their root causes is a core part of this role A strong sense of ownership, with the ability to work autonomously, take on unfamiliar areas, manage support tickets, and drive issues through to resolution Good communication skills in English (B2 Upper Intermediate or higher). You will work with international colleagues and handle customer and support requests both in writing and during meetings Experience developing or maintaining Atlassian Data Center applications (P2 Plugins, Atlassian Plugin SDK, Spring Scanner, Marketplace applications), or a strong willingness to learn the platform Recent experience with Kotlin Experience supporting a customer facing product and working directly with customer and support requests Familiarity with BI and analytics tools or the OData protocol Experience with performance profiling and optimization of large datasets Awareness of secure coding practices, including input validation, injection prevention, SSRF mitigation, dependency management, and CVE remediation Awareness of Atlassian Cloud and cloud migration paths, for example JCMA, for Data Center applications