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 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