Fullstack Java & React Developer – Kraków (Hybrid)

We are looking for a highly skilled Fullstack Developer with expertise in Java and React.js to join our Kraków-based development team. You will design, develop, and maintain scalable, high-performance web applications, contributing to both backend services and rich frontend interfaces.This role follows a hybrid working model, with 2–3 days per week onsite in Kraków.Key ResponsibilitiesBackend Development: Architect, implement, and maintain backend services using Java, Spring Boot, and related frameworksFrontend Development: Build responsive, modular, and maintainable React.js applications with a focus on component-driven designDesign and implement RESTful APIs and microservices, ensuring high performance, security, and scalabilityCollaborate with cross-functional teams to define technical requirements, system architecture, and feature implementationApply unit testing, integration testing, and end-to-end testing best practices (JUnit, Mockito, Jest, React Testing Library)Participate in code reviews, enforce coding standards, and promote best practices in clean code, SOLID principles, and design patternsTroubleshoot and optimize application performance and resolve production issuesManage CI/CD pipelines, automate deployments, and support DevOps practicesStay up-to-date with emerging technologies and frameworks to continuously improve application architectureRequired Skills and ExperienceStrong experience with Java, Spring Boot, and related backend frameworksSolid experience with React.js, Redux, or state management librariesProven experience in designing and consuming RESTful APIs and microservices architectureProficient in JavaScript, HTML5, CSS3, and modern frontend tooling (Webpack, Babel, ESLint)Experience with relational databases (MySQL, PostgreSQL) and/or NoSQL databasesFamiliarity with Git, version control workflows, and Agile/Scrum methodologiesUnderstanding of unit testing, integration testing, and test-driven development (TDD)Good problem-solving and communication skills in EnglishNice to HaveExperience with TypeScript and advanced React patterns (Hooks, Context API, Suspense)Knowledge of Docker, Kubernetes, or cloud platforms (AWS, Azure, GCP)Experience with event-driven architectures, message queues, or KafkaFamiliarity with GraphQL or WebSocket-based real-time applications