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 Responsibilities

Backend Development: Architect, implement, and maintain backend services using Java, Spring Boot, and related frameworks
Frontend Development: Build responsive, modular, and maintainable React.js applications with a focus on component-driven design
Design and implement RESTful APIs and microservices, ensuring high performance, security, and scalability
Collaborate with cross-functional teams to define technical requirements, system architecture, and feature implementation
Apply 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 patterns
Troubleshoot and optimize application performance and resolve production issues
Manage CI/CD pipelines, automate deployments, and support DevOps practices
Stay up-to-date with emerging technologies and frameworks to continuously improve application architecture

Required Skills and Experience

Strong experience with Java, Spring Boot, and related backend frameworks
Solid experience with React.js, Redux, or state management libraries
Proven experience in designing and consuming RESTful APIs and microservices architecture
Proficient in JavaScript, HTML5, CSS3, and modern frontend tooling (Webpack, Babel, ESLint)
Experience with relational databases (MySQL, PostgreSQL) and/or NoSQL databases
Familiarity with Git, version control workflows, and Agile/Scrum methodologies
Understanding of unit testing, integration testing, and test-driven development (TDD)
Good problem-solving and communication skills in English

Nice to Have

Experience 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 Kafka
Familiarity with GraphQL or WebSocket-based real-time applications

Fullstack Java & React Developer – Kraków (Hybrid)

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