Fullstack Developer (React / TypeScript / .NET) (B2B)

🏢 Summary: Full Stack Developer role with a strong frontend focus, responsible for building scalable modern web applications using React and TypeScript while contributing to backend services in .NET. The position involves delivering end-to-end features, integrating REST APIs, and ensuring high performance across frontend and backend layers in an agile environment. 🗂️ Requirements: Completed degree in Computer Science or related technical field, Strong commercial experience with React, Strong commercial experience with TypeScript, Solid understanding of modern frontend architecture and performance optimization, Experience building scalable and maintainable web applications, Good understanding of REST APIs and backend integration, Experience with C#, Experience with .NET development, Experience working in agile development environments, Understanding of software development lifecycle 📃 Skills: React, TypeScript, C#, .NET, REST, APIs, Agile, SDLC 🏢 Description: Responsibilities We are looking for a Full Stack Developer with a strong frontend focus who wants to work on modern web applications in an international environment. You will design and develop scalable business applications, primarily using React and TypeScript , while also contributing to backend services and integrations. You collaborate closely with product owners, architects, and engineering teams to deliver end-to-end features across the full stack. Your key responsibilities include: Design, develop, and maintain modern web applications using React and TypeScript . Implement responsive, user-friendly and high-performance frontend solutions. Collaborate with backend engineers and architects to deliver end-to-end features . Develop and maintain backend services and APIs using .NET technologies. Troubleshoot , debug , and optimize application performance across frontend and backend layers. Work in an agile environment with cross-functional and international teams. Support application deployment , maintenance , and continuous improvement of systems. Contribute to technical discussions and help ensure code quality and maintainability . Benefits Motivizer Benefits Platform to choose and manage all your benefits in one place. You receive a budget (550 PLN monthly). You can choose medical care package, meal tickets, sports cards (we have Multisport and on preferential terms, we have membership cards to one of the most popular Gyms), cinema tickets, shop vouchers, discounts and many more. Language Courses – you'll have access to a multi-language learning platform enabling you to practice your language skills and learn new ones! Regular and systematic further training opportunities - both internally and from external providers. We support your ongoing learning and development. Cooperation within an internal community is our everyday reality. We have networking events, coding challenges, and company parties for different occasions. Qualifications Completed university degree in Computer Science or a comparable technical field. Strong experience with React and TypeScript in production environments. Solid understanding of modern frontend architecture , performance , and best practices . Experience building scalable and maintainable web applications . Good understanding of REST APIs and backend integration concepts. Experience with C# and . NET development. Familiarity with agile methodologies and software development lifecycle . Fluent English and Polish communication skills and ability to work in international teams. Nice to have: Experience with MongoDB or other NoSQL databases. Knowledge of GraphQL and advanced API patterns. Exposure to Microsoft Azure and cloud - native architectures . Understanding of DevOps practices and CI/CD pipelines . Experience working in enterprise - scale or distributed systems environments . About Cluster Reply Cluster Reply is the Reply Group company specializing in consulting and system integration of Microsoft technologies. As a Microsoft partner, Cluster Reply is active in Germany, Austria and Switzerland and works within the Reply network with sister companies in Brazil, Great Britain, Italy as well as the USA. The company focuses on innovation and supports customers in their digital transformation. The solutions range from on-premises to cloud applications in the areas of modern workplace and security, business applications, applications and infrastructure as well as data and artificial intelligence.

🏢 Summary: Fullstack Developer role focused on building and enhancing dynamic web applications using .NET on the backend and React on the frontend. The position involves developing robust services, implementing responsive UI components, and resolving complex technical issues. The goal is to strengthen the team’s capability to deliver high-performance, scalable applications. 🗂️ Requirements: 5+ years of fullstack development experience, .NET expertise for backend development, Strong React knowledge for frontend development, Experience with Web APIs (WCF, REST), Database management experience, Proficiency in HTML, JavaScript, CSS, Understanding of message queues 📃 Skills: .NET, React, WCF, REST, WebAPI, HTML, JavaScript, CSS, SQL, Databases, MessageQueues 🏢 Description: Summary: The ideal candidate is expected to function as a Fullstack Developer, contributing both front-end and back-end functionalities with a strong focus on .NET and React technologies. The primary goal is to enhance the team's capabilities in developing seamless, robust applications. Main Responsibilities: Engage in full-stack development to create dynamic web applications. Implement the front-end components using React. Develop back-end services using .NET. Communicate effectively with team members and stakeholders in English. Investigate and resolve complex technical problems proactively. Collaborate with team members to enhance application performance and usability. Key Requirements: 5+ years of experience in fullstack development. Expertise in .NET for backend development. Strong understanding of React for frontend development. Fluent communication skills in English. Knowledge of Web APIs (WCF and REST APIs). Familiarity with database management. Competence in HTML, JavaScript, and CSS. Understanding of message queues. Nice to Have: Experience with cloud services or platforms. Familiarity with CI/CD practices. Exposure to Agile methodologies.

🏢 Summary: Fullstack Developer role focused on building and enhancing dynamic web applications using .NET on the backend and React on the frontend. The position involves developing robust, high-performance solutions, integrating APIs, and resolving complex technical issues within a collaborative team environment. Strong emphasis is placed on delivering seamless end-to-end functionality. 🗂️ Requirements: 5+ years of fullstack development experience, .NET backend expertise, Strong React knowledge, Experience with WCF and REST APIs, Database management experience, Proficiency in HTML, JavaScript, CSS, Understanding of message queues, Fluent English communication 📃 Skills: .NET, C#, React, REST, WCF, SQL, HTML, JavaScript, CSS, Databases, MessageQueues, English 🏢 Description: Summary: The ideal candidate is expected to function as a Fullstack Developer, contributing both front-end and back-end functionalities with a strong focus on .NET and React technologies. The primary goal is to enhance the team's capabilities in developing seamless, robust applications. Main Responsibilities: Engage in full-stack development to create dynamic web applications. Implement the front-end components using React. Develop back-end services using .NET. Communicate effectively with team members and stakeholders in English. Investigate and resolve complex technical problems proactively. Collaborate with team members to enhance application performance and usability. Key Requirements: 5+ years of experience in fullstack development. Expertise in .NET for backend development. Strong understanding of React for frontend development. Fluent communication skills in English. Knowledge of Web APIs (WCF and REST APIs). Familiarity with database management. Competence in HTML, JavaScript, and CSS. Understanding of message queues. Nice to Have: Experience with cloud services or platforms. Familiarity with CI/CD practices. Exposure to Agile methodologies.

🏢 Summary: Full Stack Developer role focused on building and evolving a modern web application platform with complex workflows and data-driven features. The position involves developing and maintaining both frontend and backend components, ensuring scalability, performance, and reliability. You will collaborate within a cross-functional team to deliver iterative improvements using modern development practices and AI-assisted tools. 🗂️ Requirements: Experience in full stack web application development, Hands-on experience with React, Experience with C# and .NET or comparable backend technologies, Practical experience with SQL-based databases and writing queries, Experience using AI-assisted development tools (e.g., Claude, Cursor), Solid understanding of Git and version control workflows, Ability to work with and extend existing codebases 📃 Skills: React, TypeScript, C#, .NET, SQL, Git, REST, Claude, Cursor 🏢 Description: Project overview The project is a web based application platform designed to support complex user workflows and data driven features. It focuses on performance, maintainability, and iterative delivery of new capabilities. Team You will be part of a cross functional development team consisting of full stack developers, frontend specialists, backend engineers, and QA engineers. The team works collaboratively, reviews code regularly, and follows shared development standards and branching practices. Position overview We are looking for a Full Stack Developer to contribute to the development and evolution of a modern web application platform. You will work on both frontend and backend components, focusing on building reliable, scalable features and improving existing functionality. The role combines hands on development with close collaboration across engineering and product roles. Technology stack React, TypeScript, C#, .NET, SQL based databases, Git, REST APIs, AI assisted development tools such as Claude and Cursor Responsibilities Develop and maintain frontend features using React and related technologies Build and support backend services using C# and .NET Collaborate with team members on feature design, implementation, and code reviews Work with SQL based databases to design, query, and optimize data storage Use AI assisted development tools to improve development efficiency and code quality Follow established Git workflows and branching strategies Participate in troubleshooting, debugging, and performance improvements Requirements Experience building web application platforms in a full stack role Hands on experience with React for frontend development Experience with C# and .NET or comparable backend technologies Understanding of SQL based databases and practical experience writing queries Experience using AI tools to support software development, including Claude or Cursor Solid understanding of Git, version control, and common branching flows Ability to work with existing codebases and contribute to ongoing development Nice to have Experience with cloud based environments Familiarity with CI CD pipelines Experience working on large scale or long term web platforms Exposure to performance optimization and application monitoring What We Offer: Vacation days : Up to 26 business days per year. 10 illness/special days off per year (fully paid, no medical papers needed) for all contract types Health and life insurance (Luxmed) MyBenefit platform with Multisport option Internal psychological support service English language classes from the first working day Access to external learning platforms : O’Reilly, LinkedIn Learning, Udemy, and a wide catalog of diverse internal training Flexible workplace : work from the office, from home, or choose a hybrid option Tech Skills Mentoring Program Opportunities to develop as a public speaker, mentor, or technical interviewer Fully paid idle (bench) when not involved in a project Certification reimbursement (AWS, GCP, Microsoft, etc.)

🏢 Summary: The role involves developing and maintaining scalable full-stack web applications using .NET and modern frontend frameworks. You will design robust Web APIs, optimize databases, and implement clean, testable code within CI/CD-driven environments. The position requires active participation in the full software development lifecycle for international projects. 🗂️ Requirements: Minimum 3 years commercial experience with .NET (C#, Web API, Entity Framework), Proficiency in Angular or React, Strong knowledge of JavaScript, HTML, CSS, Experience with SQL Server or PostgreSQL, Understanding of Unit Testing, Experience with Git, Experience with CI/CD pipelines, Knowledge of design patterns, Knowledge of software development best practices, Fluent English (min. B2), Availability for hybrid work mode 📃 Skills: .NET, C#, WebAPI, EntityFramework, Angular, React, JavaScript, HTML, CSS, SQL, SQLServer, PostgreSQL, UnitTesting, Git, CI/CD 🏢 Description: As a member of our development team, you will be responsible for building scalable web applications, designing robust APIs, and creating intuitive user interfaces. We value clean code, analytical thinking, and a proactive approach to technology. Our expectations: Minimum 3 years of commercial experience in .NET (C#, Web API, Entity Framework). Proficiency in Angular or React, along with JavaScript, HTML, CSS, and modern frontend libraries. Strong experience with relational databases such as SQL Server or PostgreSQL. Solid understanding of Unit Testing, Git, and CI/CD pipelines. Practical knowledge of design patterns and software development best practices. A collaborative mindset and the ability to explain complex technical issues clearly. Strong analytical skills and a "get it done" attitude. Fluent English (min. B2) for smooth collaboration with international partners. Open to work in hybrid mode. Main responsibilities: You will design, develop, and maintain scalable full-stack applications using .NET and modern frontend frameworks (Angular/React) for diverse client projects. You will be responsible for writing clean, testable code and implementing unit tests to ensure the highest software performance and reliability. You will work closely with cross-functional teams to architect robust Web APIs and optimize database schemas while following industry best practices and design patterns. You will actively participate in the full software development life cycle, including CI/CD processes and version control management, to ensure seamless project delivery.

🏢 Summary: Senior Full-Stack Developer role focused on enhancing a platform using React and TypeScript on the frontend and .NET/C# with SQL Server on the backend. The position emphasizes strong frontend expertise while maintaining sufficient backend knowledge for independent task execution. Experience with legacy systems is considered an advantage. 🗂️ Requirements: 5+ years full-stack development experience (Mid) or 10+ years (Senior), Proficiency in React, Proficiency in TypeScript, Strong knowledge of modern JavaScript, Solid knowledge of C# and .NET, Ability to work with SQL Server 📃 Skills: React, TypeScript, JavaScript, C#, .NET, SQL, SQLServer, ClassicASP 🏢 Description: Summary: A senior full-stack developer position focused on enhancing our platform through modern technologies, primarily using React and TypeScript on the frontend and .NET/C# with SQL Server on the backend. Main Responsibilities: Strengthen the focus on React and TypeScript as the primary and most critical skills, with a solid foundation in modern JavaScript. Utilize .NET/C# and SQL Server as supporting skills to ensure self-sufficiency in day-to-day tasks without primary responsibility for complex backend or database optimization. Leverage knowledge of legacy technologies, such as Classic ASP, for understanding existing logic as a nice-to-have skill. Key Requirements: At least 5 years of experience (Mid-level) or 10 years (Senior-level) in full-stack development. Proficiency in React and TypeScript. Solid foundation in modern JavaScript and C# / .NET. Nice to Have: Experience with legacy systems like Classic ASP.

🏢 Summary: Fullstack Developer role focused on building scalable web applications using ASP.NET, C#, and React, with strong emphasis on API design, event-driven architecture, and cloud-native environments. The position involves end-to-end development, CI/CD practices, containerized deployments, and collaboration in agile teams. Ideal for engineers experienced in backend services, modern frontend ecosystems, and orchestration tools. 🗂️ Requirements: Strong experience with ASP.NET, Strong experience with C#, Experience building scalable backend services and APIs, Strong experience with React, Understanding of modern frontend architecture, Experience with API design, Experience with GitLab CI/CD, Experience with RabbitMQ, Experience with Docker, Experience with Kubernetes 📃 Skills: ASP.NET, C#, React, TanStack, Tailwind, Playwright, RabbitMQ, Docker, Kubernetes, GitLab, Linux, Unity, APIs, CI/CD 🏢 Description: Role Overview We are looking for a skilled Fullstack Developer with strong backend expertise in ASP.NET and C#, combined with modern frontend development using React. The role involves building scalable web applications, designing robust APIs, and contributing to cloud-native and event-driven architectures. The ideal candidate is comfortable working across the full stack, collaborates well in agile teams, and has an interest in modern tooling, orchestration, and frontend ecosystems. Core Responsibilities • Design, develop, and maintain scalable fullstack applications • Build and maintain backend services using ASP.NET and C# • Develop responsive and modern frontend applications using React • Design and integrate APIs and asynchronous communication flows • Collaborate with developers, designers, QA, and DevOps teams • Contribute to architecture discussions and technical decisions • Ensure code quality through testing, reviews, and CI/CD practices • Participate in deployment, monitoring, and troubleshooting activities Must-Have Skills Backend • Strong experience with ASP.NET • Strong experience with C# • Experience building scalable backend services and APIs Frontend • Strong experience with React • Good understanding of modern frontend architecture and component-based development Should-Have Skills • Experience with GitLab Pipelines / CI-CD • Experience with API design and best practices Frontend Libraries & Tooling • Experience with: o TanStack o Tailwind CSS o Playwright o AI agent development (Kiro, Claude, Cursor) Messaging & Async Communication • Experience with: o RabbitMQ o Event-driven and asynchronous communication patterns • Understanding of async workflows across frontend and backend systems Infrastructure & Orchestration • Experience with: o Docker o Kubernetes • Familiarity with containerized deployments and orchestration Nice-to-Have Skills • Interest or experience in Unity / game development • Strong Linux competence Preferred Qualifications • Experience working in agile development environments • Strong problem-solving and debugging skills • Understanding of scalable and maintainable software architecture • Good communication and collaboration skills • Passion for learning modern technologies and frameworks Tech Stack Summary Area Backend: ASP.NET, C# Frontend: React Frontend Libraries: TanStack, Tailwind, Playwright Messaging: RabbitMQ Infrastructure: Docker, Kubernetes CI/CD: GitLab Pipelines Additional: Linux, API Design, Unity

🏢 Summary: Mid-level Full-stack Developer role focused on building and maintaining web and mobile applications using React and .NET technologies. The position involves developing scalable backend services, microservices, and SEO-friendly frontends integrated with CMS, within a multinational Agile environment. The role combines frontend, backend, cloud, and DevOps responsibilities with regular team collaboration. 🗂️ Requirements: 2–4 years experience as FullStack Developer, .NET 8/10 proficiency, C# proficiency, Strong React knowledge, JavaScript proficiency, TypeScript proficiency, HTML5 knowledge, CSS3 knowledge, Experience with RESTful APIs, Experience with Git, Experience with Microsoft Azure (Functions, Durable Functions, CosmosDB, ServiceBus, Application Insights), Experience with CI/CD pipelines, Experience with Agile methodologies, Communicative English (B2+) 📃 Skills: .NET, C#, React, JavaScript, TypeScript, HTML5, CSS3, REST, Git, Azure, Functions, CosmosDB, ServiceBus, ApplicationInsights, CI/CD, ReactNative, Expo, Sanity, GROQ, Redux, RxJS, Tanstack, Sentry, Firebase, Analytics 🏢 Description: Join Our Team as a Full-stack Developer (React, C#)! We are seeking a talented Mid FullStack Developer proficient in .NET and React to join our team. As part of our company culture, we value collaboration and regular in-person interactions. Our team meets every two months in our Poznań office for informal gatherings to connect, share ideas, and strengthen teamwork in a relaxed setting. You will work in multinational environment and will be responsible for designing and implementing software solutions, utilizing both front-end and back-end technologies. This role requires strong problem-solving skills, excellent communication abilities, and a passion for delivering high-quality code. Ready to take the next step in your career? Apply now and join us! Key Responsibilities: • Design and develop SEO-friendly web application, based on React and TypeScript and integrated with Sanity CMS. • Contributing to a mobile application using React Native, TypeScript and Expo . • Build and maintain microservices to enhance the web experience, including features like roadside assistance, car repair bookings, and membership management. • Develop robust and scalable backend systems using .NET 8/10, Azure ServiceBus, Functions, CosmosDB and more. • Utilize Sentry for error monitoring and Google Analytics/Firebase to track user behaviour and optimize performance. Requirements : Proven experience (2-4 years) as a FullStack Developer Proficiency in .NET (preferably .NET 8/10), C# Strong understanding of front-end technologies, including React, JavaScript, TypeScript, HTML5, and CSS3 Practical knowledge of clean-code principles and patterns, drive to write clean, testable and maintainable code Experience with RESTful APIs and Web Services Knowledge of version control systems, such as Git Excellent problem-solving and analytical skills Familiarity with Microsoft Azure platform (Functions and Durable Functions, CosmosDb, ServiceBus, Application Insights) Experience with DevOps approach and CI/CD pipelines Strong communication and interpersonal skills, communicative English (B2+) Experience with Agile development methodologies Nice to have: Experience in working with Sanity CMS and GROQ query language (or any other headless CMS) Familiarity with Figma or similar tools At least basic knowledge about Server Side Rendering and libraries like: Redux, RxJS, Tanstack Experience in working with mobile apps and practical knowledge of React Native, Expo, Expo Application Services Knowledge of microservices architecture and software integration patterns We offer: Conference/workshop budget of approximately 10000 PLN!- the budget renews every year and can be used for conferences, workshops, training programs, certifications, studies, or other development initiatives. "Fabresikowe": one-time 1000 PLN bonus to create your work space more comfortable and more tailored to your needs! Relaxing office massages In-house trainings Team events Frequent company events Free breakfast every day Free beverages, fresh fruit, snacks Chill out room English and Norwegian classes

🏢 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: Fullstack Developer role focused on designing, developing, and maintaining web applications using Angular and .NET within an NX monorepo architecture. The position involves building RESTful APIs, microservices, and responsive front-end interfaces while ensuring high code quality, performance, and security. The role also includes working with relational databases, automated testing, and CI/CD pipelines in Azure DevOps. 🗂️ Requirements: Minimum 5 years of full-stack development experience with Angular and .NET, Strong proficiency in C# and .NET Core/Framework, Experience with Entity Framework and LINQ, Solid experience with Angular (v12+) and TypeScript, Strong knowledge of RxJS, Hands-on experience with NX monorepo, Experience writing unit and integration tests with Jest, Experience with DevExtreme, Proficiency with Visual Studio, Hands-on experience with Git, Experience with Azure DevOps Services, Experience with SQL Server and query optimization, Knowledge of REST API design and HTTP standards, Understanding of software design patterns and SOLID principles, Bachelor's degree in Computer Science, Engineering, or equivalent experience 📃 Skills: Angular, TypeScript, RxJS, NgRx, .NET, C#, EntityFramework, LINQ, NX, Jest, DevExtreme, VisualStudio, Git, AzureDevOps, SQLServer, PostgreSQL, REST, HTTP 🏢 Description: We’re looking for Fullstack developer The primary objective of this role is to design, develop, and maintain full-stack web applications using Angular and .NET technologies while adhering to modern architectural best practices. Main Responsibilities: Design, develop, and maintain full-stack web applications using Angular and .NET in an NX monorepo architecture. Develop RESTful APIs and microservices using .NET Core/Framework, following Clean Architecture principles. Build responsive, user-friendly interfaces with Angular, incorporating modern patterns like RxJS and NgRx. Work with relational databases like SQL Server and PostgreSQL, designing efficient data models. Write comprehensive unit and integration tests using Jest for maintaining high code quality. Manage version control with Git and oversee CI/CD pipelines in Azure DevOps Services. Participate in code reviews to improve code quality and team practices. Collaborate with product managers, UX designers, and other developers to deliver solutions on time. Contribute to optimizing application performance and ensuring security best practices. Key Requirements: Minimum 5 years of experience in full-stack development with Angular and .NET. Strong proficiency in C#, .NET Core/Framework, Entity Framework, and LINQ. Solid experience with Angular (v12+), TypeScript, and RxJS. Hands-on experience with NX monorepo structure. Proficiency with Jest for writing unit and integration tests. Experience with the DevExtreme component library. Proficiency with Visual Studio for .NET development. Hands-on experience with Git and Azure DevOps Services. Experience with SQL Server and optimized queries. Knowledge of REST API design and HTTP standards. Understanding of software design patterns and SOLID principles. Bachelor's degree in Computer Science, Engineering, or related field (or equivalent experience). Nice to Have: Experience in agile methodologies. Familiarity with cloud services like Azure or AWS. Exposure to frontend testing frameworks like Jasmine.