Java Fullstack Developer (Java/React)

🏢 Summary: Backend-focused role involving development of scalable web applications using Java and React/Next.js. The position includes building and optimizing server-side components, APIs, and databases while ensuring performance and security. Close collaboration with cross-functional teams and end-to-end responsibility for backend quality and scalability are expected. 🗂️ Requirements: Minimum 4 years experience in similar role, Proficiency in Java server-side programming, Strong knowledge of React and Next.js, Experience with React Router and Redux, Experience with MySQL, PostgreSQL or MongoDB, Experience building scalable web applications, Knowledge of web performance and security principles, Experience with Git version control, Ability to conduct testing and debugging, English level B2 or higher 📃 Skills: Java, React, Next.js, Redux, ReactRouter, MySQL, PostgreSQL, MongoDB, SQL, NoSQL, API, REST, Git, AWS, Azure, GCP, Docker, NodeJS, Security, Testing 🏢 Description: Responsibilities: Designing, developing, and maintaining the server-side logic of web applications Implementing scalable and efficient server-side components and APIs Build React/Next.js based applications Working with relational and/or NoSQL databases to store and retrieve data efficiently Designing and optimizing database schemas for performance and scalability Integrating third-party APIs and web services to enhance application functionality Developing custom APIs to facilitate communication between front-end and back-end systems Implementing security best practices to protect against common web application vulnerabilities Conducting regular security audits and implement necessary measures Optimization: optimizing server-side code for maximum speed and scalability Monitoring and troubleshooting performance issues Collaborating with front-end developers, UI/UX designers, and other team members to ensure seamless integration of components Using version control systems (e.g., Git) to manage and track changes to the codebase Conducting thorough testing of server-side components to identify and fix bugs Collaborating with QA engineers for comprehensive testing Clear and comprehensive documentation for back-end systems and APIs Requirements: At least 4 years of experience in a similar position Proficiency in Java server-side programming Thorough understanding of React/Next.js core principles along with React router, hooks, Redux (or the like) workflows, Web performance and security Experience with database systems (e.g., MySQL, PostgreSQL, MongoDB) Proven experience in back-end development and building scalable web applications Strong analytical and problem-solving skills with attention to detail Effective communication skills to collaborate with cross-functional teams Ability to adapt to changing project requirements and technologies English at least B2 Nice to have: Familiarity with cloud platforms (e.g., AWS, Azure, GCP) Previous experience in Front-end development with Docker Experience with NodeJS Offer: Private medical care Co-financing for the sports card Constant support of dedicated consultant Employee referral program

🏢 Summary: Senior Frontend Developer role focused on building and maintaining high-performance React/Next.js applications in a cloud-based microservices environment. The position involves developing scalable web solutions, ensuring code quality, and collaborating within agile teams to deliver responsive and secure applications. 🗂️ Requirements: 5+ years of professional experience, Strong experience in JavaScript and TypeScript, Strong knowledge of React and Next.js, Experience with React Router, Hooks, and Redux or similar state management, Experience developing distributed microservices, Experience with Google Cloud Platform or other cloud environments, Experience building and troubleshooting RESTful APIs using JSON, Strong knowledge of data structures and algorithms in JavaScript, Expertise in semantic HTML, Proficiency in CSS and preprocessors (Tailwind, Styled Components, CSS Modules, SASS), Experience with unit testing and E2E testing (react-testing-library), Experience with browser debugging tools, Experience with responsive and adaptive design, English proficiency at B2 level or higher 📃 Skills: JavaScript, TypeScript, React, Next.js, Redux, REST, JSON, GCP, HTML, CSS, Tailwind, SASS, StyledComponents, CSSModules, Microservices, Jest, ReactTestingLibrary, E2E, Docker, NodeJS, GraphQL, Contentful 🏢 Description: Growth through diversity, equity, and inclusion. As an ethical business, we do what is right — including ensuring equal opportunities and fostering a safe, respectful workplace for each of us. We believe diversity fuels both personal and business growth. We're committed to building an inclusive community where all our people thrive regardless of their backgrounds, identities, or other personal characteristics. Duties description: Design, build and maintain efficient, reusable and reliable code. Build React/Next.js based applications. Ensure the best possible performance, quality, and responsiveness of applications. Identify bottlenecks and bugs, and devise solutions to mitigate and address these issues. Help maintain code quality. Participate in the agile team scrums and effectively communicate to the team the status, roadblocks, and timelines for the task at hand. Must be able to collaborate with BA, QA, developers and offshore developers to plan, design, develop, test, and maintain mobile web and desktop-based applications requested by the stakeholders. Share knowledge with the team during workshops. Requirements: 5+ years of professional experience. Strong experience in JavaScript and TypeScript. Thorough understanding of React/Next.js core principles along with React router, hooks, Redux (or the like) workflows, Web performance and security. Developing and maintaining modern distributed micro services. Development in Cloud environments (Google Cloud Platform preferred). Building, testing, and troubleshooting high volume web services using API Protocols and Data Formats (REST & JSON). Solid foundation in data structures, algorithms and its implementation in JS. Expertise with semantic HTML. Proficiency in CSS, including Tailwind, Styled Components, CSS Modules, and SASS. Expertise browser-based debugging tools. Experience with responsive and adaptive design. Experience with Testing (Unit Testing, react-testing-library, E2E). Keen understanding of web application development process and standard methodologies. Excellent communication skills. Great ownership of assigned tasks. Self-driven and proactive approach. English (B2+) Nice to have: Previous experience in Frontend development with Docker. Experience with Headless CMS (preferably Contentful). Experience with NodeJS. Knowledge of GraphQL. Missing one or two of these qualifications? We still want to hear from you! If you bring a positive mindset, we'll provide an environment where you feel valued and empowered to learn and grow. We offer: Stable employment. On the market since 2008, 1500+ talents currently on board in 7 global sites. “Office as an option” model. You can choose to work remotely or in the office. Workation. Enjoy working from inspiring locations in line with our workation policy. Great Place to Work® certified employer. Flexibility regarding working hours and your preferred form of contract. Comprehensive online onboarding program with a “Buddy” from day 1. Cooperation with top-tier engineers and experts. Unlimited access to the Udemy learning platform from day 1. Certificate training programs. Lingarians earn 500+ technology certificates yearly. Upskilling support. Capability development programs, Competency Centers, knowledge sharing sessions, community webinars, 110+ training opportunities yearly. Grow as we grow as a company. 76% of our managers are internal promotions. A diverse, inclusive, and values-driven community. Autonomy to choose the way you work. We trust your ideas. Create our community together. Refer your friends to receive bonuses. Activities to support your well-being and health. Plenty of opportunities to donate to charities and support the environment. Modern office equipment. Purchased for you or available to borrow, depending on your location.

🏢 Summary: Frontend Developer role focused on building and maintaining modern web applications using React.js. The position involves creating responsive, user-centered interfaces, integrating RESTful APIs, and delivering scalable, maintainable frontend solutions. Emphasis is placed on performance, accessibility, and clean code standards. 🗂️ Requirements: 3–4+ years commercial frontend development experience, Strong hands-on experience with React.js, Proficiency in modern JavaScript (ES6+), Solid knowledge of HTML5 and CSS3, Experience with responsive design principles, Experience integrating RESTful APIs, Understanding of UI/UX best practices, Familiarity with state management, Experience with component-based architecture, Experience with Git and collaborative workflows, Ability to write scalable and maintainable code, Strong debugging and problem-solving skills 📃 Skills: React, JavaScript, ES6, HTML5, CSS3, REST, API, Git, UI, UX 🏢 Description: Responsibilities Develop and maintain modern web applications using React.js . Create responsive and intuitive user interfaces with a strong focus on usability and user experience. Connect frontend applications with RESTful APIs and backend systems. Translate business and design requirements into scalable frontend solutions. Write clean, reusable, and maintainable code following frontend development standards. Collaborate closely with designers, product owners, and backend engineers. Optimize application performance, accessibility, and cross-browser compatibility. Requirements 3–4+ years of commercial experience in frontend development. Strong hands-on experience with React.js and modern JavaScript (ES6+). Solid knowledge of HTML5, CSS3, and responsive design principles. Experience integrating APIs and working with backend services. Understanding of UI/UX best practices and user-centered design. Familiarity with state management and component-based architecture. Experience with Git and collaborative development workflows. Ability to write efficient, scalable, and well-structured frontend code. Strong problem-solving and debugging skills.

🏢 Summary: Full-Stack / Backend Developer role focused on building and maintaining scalable applications and REST APIs that support client products. The position involves developing new integrations, enhancing existing backend and frontend systems, and improving platform performance and reliability. You will contribute to architecture improvements and work within a cloud-based environment. 🗂️ Requirements: Minimum 3 years commercial experience, Experience with Java, Experience with Spring Boot, Experience with AWS, Experience with MongoDB, Experience with PostgreSQL, Experience with React.js, Experience designing REST APIs, Knowledge of backend architecture, Experience with cloud environments, Understanding of clean code principles, Experience working in Agile environment 📃 Skills: Java, SpringBoot, AWS, MongoDB, PostgreSQL, React, REST, Agile, Cloud, Architecture 🏢 Description: We are looking for an experienced Full-Stack / Backend Developer to join our team and help build scalable applications and APIs supporting our clients’ products. You will work on both backend and frontend solutions, contributing to product development, system improvements, and ongoing platform stability. Your Responsibilities Develop new APIs to support client integrations and business features. Maintain and enhance existing backend and frontend applications. Fix bugs and improve application performance and reliability. Upgrade and support operational aspects of the platform. Identify opportunities to improve product quality, architecture, and development processes. Collaborate with developers, product teams, and stakeholders to deliver high-quality solutions. Participate in code reviews and contribute to best engineering practices. Required Skills Minimum 3 years of commercial experience with: Java Spring Boot AWS MongoDB PostgreSQL React.js Experience designing and developing REST APIs. Knowledge of backend architecture and modern web applications. Experience working with cloud-based environments (AWS). Understanding of software development best practices and clean code principles. Ability to work in an Agile development environment.

🏢 Summary: Frontend React Developer role focused on building and scaling modern web applications using React and Next.js in distributed, cloud-based environments. The position involves developing reusable components, integrating with APIs and cloud services, and ensuring high performance, security, and code quality through testing and best practices. The role requires strong experience in scalable architectures and collaboration within microservices-based systems. 🗂️ Requirements: 5+ years of commercial experience with React, Strong knowledge of JavaScript and TypeScript, Practical experience with React hooks, routing, and state management, Experience in distributed systems or microservices environments, Experience with cloud platforms (GCP preferred), Experience building scalable applications consuming REST APIs and JSON, Knowledge of data structures and algorithms, Proficiency in HTML and modern CSS approaches, Experience with automated testing (unit, integration, end-to-end), Ability to debug and optimize applications using browser developer tools, Experience building responsive web interfaces 📃 Skills: React, Next.js, JavaScript, TypeScript, HTML, CSS, Tailwind, SASS, CSSModules, REST, JSON, GCP, Microservices, UnitTesting, IntegrationTesting, E2E, BrowserTools, DataStructures, Algorithms 🏢 Description: We are looking for a Frontend React Developer for our client – a global technology consulting company focused on data, analytics, and cloud-based solutions, supporting international organizations in building scalable digital products. They operate in a distributed environment, combining strong engineering practices with a business-oriented mindset to deliver impactful solutions across multiple industries. Your responsibilities Build and enhance modern web applications using React and Next.js Create reusable components and contribute to scalable frontend architecture Work closely with cross-functional teams including backend engineers, data specialists, and product stakeholders Improve performance, security, and overall user experience of applications Connect frontend layers with APIs and cloud-based services Maintain high development standards through testing and clean coding practices. Requirements At least 5 years of hands-on experience with React in commercial projects Strong command of JavaScript and TypeScript Practical understanding of React fundamentals, including hooks, routing, and state management solutions Experience working in distributed systems or microservices environments Exposure to cloud platforms (GCP experience is an advantage) Background in developing scalable applications that consume REST APIs and work with JSON data Solid grasp of core programming concepts such as data structures and algorithms Good knowledge of HTML and modern CSS approaches (e.g. Tailwind, SASS, CSS Modules, or similar tools) Experience with automated testing (unit, integration, and end-to-end) Ability to debug and optimize applications using browser developer tools Experience in building responsive and user-friendly interfaces across devices Strong communication skills and experience working in collaborative, distributed teams Self-driven approach with a strong sense of ownership English proficiency at B2 + level or higher.

🏢 Summary: Full-Stack Front-End Developer role focused on building and enhancing modern, cloud-based web applications with strong emphasis on user experience, performance, and scalability. The position involves developing frontend features in React.js, integrating with Java backend services, and working within AWS environments. The role includes maintaining existing applications, optimizing performance, and contributing to best development practices in an Agile team. 🗂️ Requirements: Minimum 3 years commercial experience with React.js, Minimum 3 years commercial experience with JavaScript, Minimum 3 years commercial experience with TypeScript, Minimum 3 years commercial experience with Java, Minimum 3 years commercial experience with AWS, Experience building responsive web applications, Experience integrating frontend applications with APIs, Understanding of frontend architecture, Knowledge of Agile methodologies 📃 Skills: React.js, JavaScript, TypeScript, Java, AWS, API, Agile 🏢 Description: We are looking for a Full-Stack Front-End Developer who is passionate about building modern, cloud-based applications and delivering excellent user experiences. You will work on developing and maintaining several existing applications and services, focusing on improving usability, performance, and scalability in a cloud environment. Responsibilities Maintain and develop high-quality user experiences across multiple web applications and services. Build and enhance frontend features using React.js and modern JavaScript frameworks. Collaborate with backend services developed in Java . Improve application performance, usability, and responsiveness. Work with cloud-based environments hosted on AWS . Fix bugs, optimize existing solutions, and introduce improvements. Collaborate closely with developers, product teams, and stakeholders. Contribute to code reviews and follow best development practices. Required Skills Minimum 3 years of commercial experience with: React.js JavaScript TypeScript Java AWS Experience building responsive and user-focused web applications. Understanding of frontend architecture and modern UI development practices. Experience integrating frontend applications with APIs. Knowledge of Agile development methodologies. Strong problem-solving and communication skills.

🏢 Summary: Senior Fullstack Developer role focused on building a greenfield solution using Java 17+ and Spring Boot on the backend and React on the frontend. The position involves end-to-end development, architecture co-creation, REST API design, and ensuring code quality within an Agile environment. The role requires close collaboration with business stakeholders and active participation in technical decision-making. 🗂️ Requirements: Minimum 8 years of experience in Java 17+, Minimum 5 years of experience with React, Minimum 5 years of experience with Spring Boot, Minimum 5 years of experience with JPA, Experience in building full-stack applications, Practical experience in REST API design, Experience with relational databases, Experience working in Agile methodology, Ability to analyze business requirements technically, Very good English skills 📃 Skills: Java, Spring, SpringBoot, React, JPA, REST, SQL, Agile, Selenium, Liquibase, Maven, Cucumber 🏢 Description: Responsibilities: Design and development of applications in fullstack architecture (backend + frontend) Creation and development of the backend layer based on Java 17+ and Spring Boot Building and developing the user interface in React with an emphasis on UX and readability Modeling and implementation of the data access layer (JPA) Cooperation with the business team in analyzing and clarifying requirements Breaking down requirements into user stories and estimating work Designing and implementing end-to-end tests Ensuring code quality (code review, best practices, clean code) Co-creating the architecture of a greenfield project solution Collaborating in an Agile environment (refinements, sprint planning, daily, retrospectives) Participating in technological decision-making Requirements: Minimum 8 years of experience in Java programming (version 17+) Minimum 5 years of experience with: React, Spring Boot and JPA Experience in building full-stack applications (backend + frontend) Practical knowledge of REST API design Experience in working with relational databases Ability to work with business requirements and their technical analysis Experience in working with Agile methodology Very good knowledge of English (working in an international environment) Independence, proactivity, and ability to make technical decisions Nice to have: Experience with: Selenium, Liquibase for database versioning, Maven and Cucumber for testing Offer: Private medical care Co-financing for the sports card Constant support of dedicated consultant Employee referral program

🏢 Summary: Senior Fullstack Developer role focused on designing and building a greenfield application using Java 17+ and Spring Boot on the backend and React on the frontend. The position involves end-to-end development, architectural decisions, REST API design, and ensuring code quality within an Agile environment. The role also includes close collaboration with business stakeholders and participation in technical decision-making. 🗂️ Requirements: Minimum 8 years of experience with Java 17+, Minimum 5 years of experience with React, Minimum 5 years of experience with Spring Boot, Minimum 5 years of experience with JPA, Experience building fullstack applications, Practical experience designing REST APIs, Experience with relational databases, Experience working in Agile methodology, Ability to analyze business requirements technically, Very good English proficiency 📃 Skills: Java, Spring, SpringBoot, React, JPA, REST, SQL, Agile, Selenium, Liquibase, Maven, Cucumber 🏢 Description: Responsibilities: Design and development of applications in fullstack architecture (backend + frontend) Creation and development of the backend layer based on Java 17+ and Spring Boot Building and developing the user interface in React with an emphasis on UX and readability Modeling and implementation of the data access layer (JPA) Cooperation with the business team in analyzing and clarifying requirements Breaking down requirements into user stories and estimating work Designing and implementing end-to-end tests Ensuring code quality (code review, best practices, clean code) Co-creating the architecture of a greenfield project solution Collaborating in an Agile environment (refinements, sprint planning, daily, retrospectives) Participating in technological decision-making Requirements: Minimum 8 years of experience in Java programming (version 17+) Minimum 5 years of experience with: React, Spring Boot and JPA Experience in building full-stack applications (backend + frontend) Practical knowledge of REST API design Experience in working with relational databases Ability to work with business requirements and their technical analysis Experience in working with Agile methodology Very good knowledge of English (working in an international environment) Independence, proactivity, and ability to make technical decisions Nice to have: Experience with: Selenium, Liquibase for database versioning, Maven and Cucumber for testing Offer: Private medical care Co-financing for the sports card Constant support of dedicated consultant Employee referral program

🏢 Summary: Fullstack Developer role for an international heating solutions client, focused on building advanced planning applications using React and Java. The position involves developing backend APIs, responsive interfaces, and managing the full platform lifecycle with CI/CD and cloud technologies. The role requires strong experience in enterprise Java, modern frontend frameworks, automated testing, and AI-assisted development workflows. 🗂️ Requirements: Strong proficiency in React, Strong proficiency in Next.js, Strong proficiency in Node.js with SSR, Advanced programming experience in Java, Advanced programming experience in TypeScript, Experience with Spring Boot, Experience integrating LLMs and AI tools, Experience designing and consuming REST APIs, Experience with relational databases, Experience with NoSQL databases, Experience with MS Azure, Experience with Docker, Experience with Kubernetes, Experience with Terraform, Experience with GitHub Actions, Experience with Gradle, Experience writing Unit tests, Experience writing Integration tests, Experience writing E2E tests, Understanding of Agile (Scrum or Kanban), English level minimum B2, Willingness to travel occasionally to Katowice 📃 Skills: React, Next.js, Node.js, Java, TypeScript, JavaScript, Spring, SpringBoot, REST, SQL, NoSQL, Azure, Docker, Kubernetes, Terraform, GitHubActions, Gradle, LLM, AI, Scrum, Kanban, Vue.js 🏢 Description: About the project For an international client from the heating solutions industry, we are looking for an experienced Fullstack Developer who feels comfortable working with React and Java. Our expectations Strong proficiency in React, Next.js, and Node.js, including Server-Side Rendering (SSR). Advanced, hands-on programming experience with both Java and TypeScript / JavaScript. Deep knowledge of enterprise software development using Java and Spring Boot technologies. Experience integrating LLMs and AI tools into daily workflows to optimize development speed. Mastery of REST APIs and experience with relational/NoSQL databases, especially within MS Azure. Hands-on experience with Docker, Kubernetes, Terraform, and pipeline automation via GitHub Actions and Gradle. Direct experience writing automated Unit, Integration, and E2E tests. Strong understanding of Agile principles including Scrum or Kanban. Very goo command of English (min. B2 level) Willingness to undertake occasional travel to the client's office (Katowice) approximately once per quarter. Welcome Skills Experience with Vue.JS. Key tasks Design advanced planning applications in close collaboration with cross-functional teams. Develop robust backend APIs for resource scheduling, allocation logic, and core modules. Create responsive interfaces focused on performance, security, data visualization, and accessibility. Build your own AI-based work environment using advanced developer tools to maximize efficiency. Manage the platform lifecycle from architectural strategy to operations and CI/CD practices. Design and implement automated test scenarios to guarantee platform success. Maintain active communication with the Technical Product Owner and Product Management organization to align priorities.

🏢 Summary: Fullstack Developer role focused on building and maintaining web applications using Java on the backend and React on the frontend. The position involves API design, database integration, and unit testing to deliver robust, high-quality software. Candidates will work across the full stack, contributing to both development and code quality processes. 🗂️ Requirements: 2+ years of Java programming experience, Strong knowledge of SQL, Experience with API definition, Proficiency in Git, Experience with JUnit testing, Proficiency in React, Proficiency in Next.js 📃 Skills: Java, React, Next.js, SQL, API, Git, JUnit 🏢 Description: Introduction & Summary: We are seeking a skilled Fullstack Developer specializing in Java and React. The ideal candidate will have over 2 years of experience in Java programming along with a solid understanding of modern frontend frameworks. The role requires proficiency in SQL and API definition, as well as experience with Git and Junit, making it essential for creating robust applications. Main Responsibilities: The Fullstack Developer will take on a pivotal role in our development team, responsible for both backend and frontend tasks. Develop and maintain web applications using Java and React. Define and implement APIs for seamless integration. Collaborate with cross-functional teams to design and deliver software solutions. Conduct unit testing to ensure high-quality code. Utilize Git for version control and collaboration. Key Requirements: 2+ years of experience in Java programming. Strong knowledge of SQL. Experience with API definition. Proficiency in Git. Experience with Junit testing. Proficient in frontend frameworks - React and Next.js. Nice to Have: Experience with Kafka and Spring Kafka (very nice to have). Some experience in microservices development. Familiarity with MongoDB. Experience with Spring Data JPA.