Senior Full Stack Developer

🏢 Summary: Full-time Senior Full Stack Developer role focused on building scalable, data-driven platforms for financial and enterprise sectors using Node.js and React. The position involves designing microservices, developing RESTful APIs, and creating responsive front-end applications in a hybrid work model (Warsaw). 🗂️ Requirements: 5+ years experience as Senior Full Stack Developer, Strong expertise in Node.js, Strong expertise in React, Experience with Express.js, Experience building RESTful or GraphQL APIs, Knowledge of OAuth and JWT authentication, Proficiency in Redux, HTML5, CSS3, ES6+, Experience with Vite, Webpack or Babel, Experience with MySQL or PostgreSQL, Experience with AWS, Azure or GCP, Experience with Docker and Kubernetes, Proficiency with Git 📃 Skills: Node.js, React, Express.js, GraphQL, REST, OAuth, JWT, Redux, HTML5, CSS3, JavaScript, ES6, Vite, Webpack, Babel, MySQL, PostgreSQL, AWS, Azure, GCP, Docker, Kubernetes, Git, SQL, MongoDB, CI/CD 🏢 Description: Senior Full Stack Developer (Node.js + React) 💰 Salary: 23,000-24,800 PLN/Month 💻 Warsaw, Poland (Hybrid - 3 days in office, 2 days remote) 🕦 Full-time ☑️ B2B or CoE We’re looking for a Senior Full-Stack Developer to join a fast-growing international tech company focused on building modern, data-driven platforms that power digital transformation in the financial and enterprise sectors. Requirements: 5+ years of experience as a Senior Full Stack Developer with significant expertise in Node.js and React. Strong experience in building server-side applications using Node.js and Express.js. Hands-on experience with API development and integration, particularly with GraphQL or RESTful services. Strong knowledge of authentication and authorization mechanisms (OAuth, JWT, session-based). Front-end proficiency in React.js, Redux, HTML5, CSS3, and modern JavaScript (ES6+). Familiarity with front-end build tools such as Vite, Webpack, and Babel. Strong experience with databases such as MySQL and  PostgreSQL. Experience with cloud platforms (AWS, Azure, or GCP), as well as containerization and orchestration tools such as Docker and Kubernetes. Strong experience using Git and version control systems. Proficiency in English (both written and spoken). Key Responsibilities: Design, build, and maintain scalable, high-performance server-side applications and RESTful APIs using Node.js and Express.js. Develop and maintain interactive, responsive user interfaces using React.js, Redux, and modern JavaScript (ES6+). Lead the design and implementation of scalable architectures and microservices. Work closely with database engineers to design efficient schemas and manage data interactions using SQL databases or MongoDB. Ensure reliable deployments and smooth release of updates using CI/CD pipelines and Docker. Write unit and integration tests and optimize performance to ensure high-quality code. Collaborate closely with cross-functional teams to define and implement technical solutions. Improve system performance, reliability, and long-term maintainability through optimization and best practices. Get to know DevsData: We are a technology consulting company and a recruitment agency, delivering software solutions to clients from Europe and the US. We work 100% remotely, in an international team, including people from Asia, London, or San Francisco. We employ people with experience in international corporations as well as students of the best technical and business universities. Find out more: https://devsdata.com/

🏢 Summary: Senior Full Stack Developer role focused on building and maintaining a complex web application for visualization of financial relationship networks using React, Node.js, GraphQL, and graph databases. The position involves end-to-end development, backend integration, graph data visualization, and architectural decision-making in a fully remote B2B setup. Candidates will work with scalable microservices, streaming systems, and advanced frontend performance optimization. 🗂️ Requirements: Minimum 7 years of commercial software development experience, Expert knowledge of React, Advanced TypeScript skills, Strong experience with Redux, Experience optimizing frontend performance for large datasets, Solid Node.js backend development experience, Experience building REST APIs, Experience building GraphQL APIs, Knowledge of application architecture and design patterns, Experience with Storybook, English level B2/C1, Ability to make technical decisions independently 📃 Skills: React, Node.js, TypeScript, Redux, GraphQL, REST, Storybook, MongoDB, Neo4j, Kafka, D3.js, GoJS, Cytoscape, AGGrid, Cypher, Gremlin, Neptune 🏢 Description: Senior Full Stack Developer (React / Node.js / Graph Data) Stawka: 190 – 200 PLN / godz. netto (+ VAT) Forma współpracy: Kontrakt B2B Model pracy: 100% Zdalnie (w ramach zespołu w Polsce) Godziny pracy: 9:00 – 17:00 (Warsaw Time) O projekcie Dołączasz do nowo powstającego, zespołu projektowego w Polsce, który przejmuje całkowitą odpowiedzialność za end-to-end rozwój zaawansowanej aplikacji webowej opartej na technologii baz grafowych. Przenosimy "serce" systemu do Polski. Aplikacja służy do wizualizacji złożonych sieci powiązań finansowych . Szukamy mocnego zawodnika – Seniora z krwi i kości, który bez problemu połączy skomplikowany świat danych backendowych z najwyższej klasy interfejsem użytkownika. Twój profil: Silny Full Stack (Mocny React + Solidny Node.js) W tej roli łączysz dwa światy. Z jednej strony potrzebujemy Twojej eksperckiej wiedzy w React , aby płynnie renderować ogromne ilości danych i sieci powiązań grafowych. Z drugiej strony Twój kod w Node.js będzie stanowił "serce" komunikacji między API GraphQL a rozbudowanym ekosystemem danych (Kafka, MongoDB, Neo4j). Twoje zadania: React Excellence: Projektowanie i rozwój zaawansowanych, wydajnych aplikacji webowych przy użyciu React i TypeScript. Wizualizacja Danych Grafowych: Transformacja surowych danych z bazy grafowej na interaktywne, responsywne komponenty UI (z użyciem D3.js, GoJS lub pokrewnych). Rozwój Core Backend: Projektowanie, utrzymanie i optymalizacja skalowalnych mikroserwisów w Node.js (TypeScript). Ewolucja GraphQL & Integracja: Projektowanie optymalnych schematów i wydajnych resolverów, które spajają frontend z bazami NoSQL/Neo4j oraz systemami streamingowymi (Kafka). Quality & Architecture Leadership: Aktywny udział w podejmowaniu decyzji architektonicznych, dbanie o czystość kodu (rygorystyczne Code Review) oraz rozwój reużywalnych komponentów w Storybook. Wymagania (Must Have) – Szukamy Eksperta: Minimum 7 lat komercyjnego doświadczenia w rozwoju oprogramowania. Expert React & TypeScript: Głęboka znajomość nowoczesnych wzorców React, zaawansowanego zarządzania stanem ( Redux ) oraz optymalizacji wydajności frontendowej przy renderowaniu dużych, zagnieżdżonych zestawów danych. Solidny Node.js & TypeScript: Praktyczne doświadczenie w budowaniu stabilnych, produkcyjnych systemów backendowych i wydajnych API (REST / GraphQL ). Architektura & Narzędzia: Bardzo dobra znajomość architektury aplikacji, wzorców projektowych oraz praca ze Storybook . Język angielski: Minimum B2/C1 – warunek konieczny do codziennej, płynnej współpracy z interesariuszami z USA i Holandii. Zdolność do brania odpowiedzialności: Szukamy osoby z samodzielnym podejściem, która potrafi podjąć decyzję techniczną i dba o stabilność całego systemu. Mile widziane (Mile widziane): Praktyczna znajomość baz NoSQL oraz baz grafowych (np. MongoDB, Neo4j , AWS Neptune) wraz z zapytaniami Cypher/Gremlin. Doświadczenie z systemami event-driven / streamingowymi (np. Apache Kafka ). Zaawansowana znajomość AG Grid pod kątem rozbudowanego raportowania. Doświadczenie z bibliotekami do wizualizacji danych (D3.js, GoJS, Cytoscape). Co oferujemy? Realny wpływ: Nie jesteś tylko wykonawcą zadań. Jako Senior masz decydujący głos w kwestiach architektonicznych i technologicznych. Unikalny Stack Technologiczny Stabilność i profesjonalizm plus praca zdalna Zainteresowany? Aplikuj

🏢 Summary: Full Stack Development Lead role focused on delivering end-to-end solutions using React and C# .NET Core in a cloud-driven, microservices-based environment. The position combines hands-on development with architectural input and technical leadership in a fully remote B2B setup. The role involves close collaboration with cross-functional teams and contribution to modern DevOps and data workflows. 🗂️ Requirements: Proven full-stack experience with React, TypeScript, C# .NET Core, Strong knowledge of microservices architecture, Understanding of distributed systems, Experience with CI/CD pipelines, Experience with cloud platforms (Azure preferred), Experience with containers, Familiarity with DevOps practices, Ability to design APIs and event-driven components 📃 Skills: React, TypeScript, C#, .NET, Microservices, CI/CD, Azure, Docker, DevOps, PySpark, PowerBI, APIs 🏢 Description: Start Date: ASAP / Within 1 Month / Flexible Work Model: 100% remote Contract Type: B2B (160-180 PLN/h + VAT) We are looking for an experienced Full Stack Development Lead who will take ownership of end‑to‑end solutions across React and C# .NET Core while contributing to technical direction and supporting a collaborative engineering culture. This role is ideal for a strong Senior Full Stack Developer who is ready to expand into leadership responsibilities, work closely with cross‑functional teams, and influence architectural decisions in a modern, cloud‑driven environment. Expectations Proven experience in full‑stack development using React, TypeScript, and C# .NET Core. Good understanding of microservices , distributed systems, and CI/CD pipelines. Exposure to cloud platforms (Azure preferred), containers, and modern DevOps practices. Experience with data workflows (pyspark) or BI solutions (Power BI) is a strong advantage. Ability to collaborate with technical and business stakeholders and take initiative in solution design. Responsibilities Contribute to the design and delivery of full‑stack applications using React and C# .NET Core. Support architectural discussions around microservices, APIs, and event‑driven components. Collaborate with data engineers on pyspark workflows and Power BI reporting enhancements. Promote engineering best practices, code quality, and maintainable development patterns. Mentor team members and support planning, collaboration, and continuous improvement efforts. What We Offer Medicover healthcare package Multisport card Access to an e-learning platform Group life insurance

🏢 Summary: Senior Fullstack Developer role focused on extending a HubSpot-based CRM with new frontend, backend, and integration functionalities in a fully remote setup. The position involves building custom modules, managing license and trial features, and ensuring reliable integrations between internal and external systems. The developer will take ownership of data flows, webhooks, and system reliability within a small cross-functional team. 🗂️ Requirements: Minimum 5 years of experience as Fullstack Developer, Strong knowledge of React, Strong knowledge of TypeScript, Solid experience with Node.js, Experience with API development, Hands-on experience with webhooks, Experience with system integrations, Ability to extend existing backend codebases, Experience with AI-assisted coding tools, English C1 level, Polish B2 level 📃 Skills: React, TypeScript, Node.js, APIs, Webhooks, HubSpot, CRM, LMS, Authentication, Integrations, Monitoring, Observability, Claude 🏢 Description: Senior Fullstack Developer (React / Node.js) – Fully Remote Location: Fully remote Working hours: 10:00–18:00 (UK time), no travel required Rate: PLN 120–160 / hour Project duration: Initial 2 months, extension very likely Client: International financial institution Process: 2 interview stages Team: 2 Developers, Project Manager, Architect About the Role We are looking for an experienced Senior Fullstack Developer to join a small, cross-functional team working on the expansion of an existing CRM system. The project focuses on extending a HubSpot-based solution with new frontend, backend, and integration functionalities. You will play a key role in designing and building a new custom HubSpot application for internal users, developing license and trial management features, and integrating multiple internal and external systems. The role combines hands-on development with ownership of integrations and data flow reliability. Responsibilities Design and develop a new custom module within an existing HubSpot application Build user-facing interfaces for internal HubSpot users Implement a management panel for customer trials and licenses Integrate the application with existing internal APIs Identify and implement missing backend functionalities Develop integration code in Node.js connecting LMS webhooks with the authentication system Automate user account creation based on LMS-triggered events Automate user roles and permissions assignment based on learning system data Ensure data consistency, reliability, and observability across systems Handle error management, retries, and monitoring of webhook-based flows Requirements Minimum 5 years of professional experience as a Fullstack Developer Very strong knowledge of React and TypeScript Solid experience with Node.js and API development Hands-on experience with webhooks and system integrations Ability to read, understand, and extend existing backend codebases Practical experience using Claude Code or similar AI-assisted coding tools English proficiency at C1 level (daily collaboration with international clients) Polish proficiency at B2 level or higher (internal team communication) What We Offer Fully remote work Competitive hourly rate: PLN 120–160 Sports card (Multisport or equivalent) Private medical healthcare Access to learning and training platforms Small, experienced team with a clear technical direction High likelihood of project extension after 2 months

🏢 Summary: Senior Full Stack Developer role focused on architecting and delivering high-performance web applications using React and Node.js. The position involves leading system design, building scalable front-end and back-end solutions, and overseeing cloud-based deployments and DevOps processes. The role includes technical ownership of microservices, APIs, databases, and application performance in a hybrid Warsaw-based setup. 🗂️ Requirements: 7+ years full stack development experience, 2+ years in senior or technical lead role, Expert-level React.js with Hooks and Redux, Advanced JavaScript ES6+ proficiency, Strong Node.js and Express.js experience, Experience designing REST or GraphQL APIs, Experience with OAuth, JWT, sessions, RBAC, Database design and optimization with PostgreSQL, MySQL, or MongoDB, Hands-on Docker experience, Experience with AWS, Azure, or GCP, CI/CD pipeline management experience, Proficiency with Git workflows, Bachelor’s or Master’s in Computer Science or related field 📃 Skills: React, Redux, JavaScript, HTML5, CSS3, Node.js, Express, GraphQL, REST, OAuth, JWT, RBAC, PostgreSQL, MySQL, MongoDB, Docker, Kubernetes, AWS, Azure, GCP, Git, CI/CD, Webpack, Babel, Vite 🏢 Description: 🧩 About the Company Our client is a rapidly growing US-based technology firm with global operations. With a strong commitment to innovation and quality engineering, the company is building a new engineering hub in Warsaw. This is your opportunity to join a high-performing team and play a pivotal role in developing next-generation digital solutions for the private capital markets. 📍 Location & Setup Start remotely and transition to a hybrid model based in Warsaw (3 days/week in the office in the coming months). 🧠 The Role: Senior Full Stack Developer (React & Node.js) We’re looking for an expert-level Senior Full Stack Developer with at least 7 years of professional experience in designing, architecting, and delivering high-performance web applications. You will take ownership of complex technical challenges across both the front-end and back-end, drive architectural decisions, and provide technical leadership and mentorship within the software development lifecycle. 🔧 Key Responsibilities Technical Leadership: Architect and develop scalable, responsive UIs with React.js, Redux, and modern JavaScript (ES6+). System Design: Design, build, and scale advanced server-side applications, microservices architecture, and RESTful/GraphQL APIs with Node.js and Express. Data Architecture: Lead database design, optimization, and integration strategies (PostgreSQL, MySQL, or MongoDB). Quality Assurance: Define testing strategies, write robust unit/integration tests, and establish efficient debugging protocols for the team. DevOps & Deployment: Oversee and optimize CI/CD pipelines, containerization using Docker, and cloud deployments. Agile Mentorship: Lead agile collaboration with product managers, designers, and engineers, while mentoring mid-level and junior developers. Performance: Proactively monitor system performance, identify bottlenecks, and maintain high-availability production-grade applications. Standards: Establish and maintain comprehensive technical documentation and coding standards. 📌 What We’re Looking For Front-End: Expert-level experience with React.js, Hooks, Redux, and complex component-based architecture. Deep mastery of HTML5, CSS3, and ES6+. Advanced configuration and optimization experience with build tools like Webpack, Babel, or Vite. Back-End: Senior-level proficiency in Node.js & Express.js for enterprise applications. Extensive API design and architecture experience (GraphQL highly preferred, alongside REST). Deep understanding and implementation experience with advanced security and authentication protocols: OAuth, JWT, sessions, and RBAC. Databases & DevOps: Proven experience in scaling and optimizing relational and non-relational databases (PostgreSQL, MySQL, or MongoDB). Solid hands-on experience with Docker; Kubernetes experience is highly advantageous. Demonstrated experience designing and deploying applications on cloud platforms (AWS, Azure, or GCP). Advanced proficiency with Git workflows and driving Agile/Scrum methodologies. 🎓 Qualifications Bachelor’s or Master’s in Computer Science or a related field. 7+ years of hands-on experience in full stack development. 2+ years of experience in a senior or technical lead capacity. Proven track record of architecting, deploying, and maintaining high-traffic production applications. 💡 Soft Skills Strategic, analytical thinker and highly effective problem-solver. Strong technical leadership, team collaboration, and cross-functional communication skills. Self-motivated with excellent time management and the ability to drive projects autonomously. Passion for continuous learning, adopting new technologies, and sharing knowledge with the team. 🎁 What’s Offered Competitive salary up to $6,200 USD/month. Hybrid remote role with 3 days form office in the heart of Warsaw Generous Paid Time Off (PTO). Comprehensive full benefits package. The unique chance to shape the technical foundation of a new engineering hub and lead high-impact projects. A supportive, innovation-driven work environment that values technical excellence.

🏢 Summary: Senior Full-Stack Engineer role focused on designing and evolving scalable SaaS systems using Node.js and React in a 100% remote B2B model. The position involves architectural decision-making, production system ownership, performance optimization, and mentoring within a distributed team. The offer targets experienced engineers capable of leading technical initiatives and ensuring system reliability at scale. 🗂️ Requirements: Minimum 10 years of professional software development experience, Proven experience with SaaS-based systems, Strong knowledge of scalable systems and software architecture, Hands-on experience with Node.js, Hands-on experience with React, Experience designing or evolving system architectures, Experience working with production systems and real users, Experience with monitoring, debugging, and performance optimization, Ability to own major system components and lead technical decisions, Excellent English proficiency 📃 Skills: Node.js, React, JavaScript, SaaS, AWS, GCP, Azure, CI/CD, DevOps, Architecture, Monitoring, Debugging, Performance, Scalability 🏢 Description: For a client, we are looking for a Senior Full-Stack Engineer (NodeJS + React)! Salary: 24 000-27 000 net+VAT B2B 100% remote RESPONSIBILITIES Architecture, production, and reliability experience: Proven experience designing systems from scratch or significantly evolving existing architectures Experience working on production systems with real users Strong understanding of architectural trade-offs (performance, scalability, cost, and maintainability) Experience with monitoring, debugging, and performance optimization in production environments Familiarity with handling production issues and incidents Ownership and leadership: Experience owning major system components or leading technical decisions Ability to work independently with minimal supervision Experience mentoring junior or mid-level developers and collaborating within a team REQUIREMENTS At least 10 years of professional software development experience Proven experience working with SaaS-based systems Strong understanding of scalable systems and software architecture Hands-on experience with Node.js and React Excellent English proficiency and strong communication skills NICE TO HAVE Experience with cloud platforms such as AWS, GCP, or Azure Familiarity with CI/CD pipelines and modern DevOps practices Experience working in distributed or remote teams Product mindset — ability to understand business requirements and translate them into technical solution WHAT DO WE OFFER ON THIS PROJECT? Cooperation based on a B2B contract and rate: 24 000-27 000 PLN/hour 100% remote work The support of a dedicated mentor. In the relationship, we focus on direct communication. When you join speedapp, you will be put in touch with a dedicated mentor who will make sure that you enjoy working with us and with the client. Events and integration meetings, as well as participation in various initiatives, e.g., sports. Access to the benefits offering (medical care, life insurance, Multisport card). WHAT DOES THE RECRUITMENT PROCESS LOOK LIKE? Application: Apply and submit your CV. After the application review, the recruiter will contact selected candidates by phone. Screening: Have a conversation with a speedapp recruiter about your experience. Next steps: The speedapp recruiter will explain the recruitment process for the specific position. The speedapp recruiter will stay in touch with you throughout the entire process. ABOUT SPEEDAPP At speedapp, we believe that an organization is only as good as the people who make it up. We are a team of IT experts and other professionals working for our clients around the world (including Israel, Austria, USA). We go far beyond the HR category. We build IT teams and also help manage them. 👉 10 years of experience 👉 +100 clients worldwide +300 hires per year 💎 We have won the prestigious "Forbes Diamonds" award four times (2022, 2023, 2024, 2025). We are a member of the European Fast Growth Icons network and FinTech Poland. We are ranked 18th among the 100 fastest growing companies 2023 by Clutch. DO YOU HAVE ANY QUESTIONS? Contact the recruiter responsible for this process directly. Iga Olszewska-Magnowska Senior IT Delivery Consultant iga.olszewska@speedapp.pl

🏢 Summary: Seeking a Senior Full-Stack Engineer (NodeJS + React) to design, evolve, and maintain scalable SaaS systems in a fully remote B2B engagement. The role focuses on architecture, production reliability, and technical ownership of key system components. You will work on real-user production systems, ensuring performance, scalability, and maintainability. 🗂️ Requirements: Minimum 10 years of professional software development experience, Proven experience with SaaS-based systems, Strong knowledge of scalable systems and software architecture, Hands-on experience with Node.js, Hands-on experience with React, Experience designing or evolving system architectures, Experience working with production systems, Experience with monitoring, debugging, and performance optimization, Fluent English proficiency 📃 Skills: Node.js, React, JavaScript, SaaS, Architecture, Scalability, Monitoring, Debugging, CI/CD, AWS, GCP, Azure 🏢 Description: For a client, we are looking for a Senior Full-Stack Engineer (NodeJS + React)! Salary: 24 000-27 000 net+VAT B2B 100% remote RESPONSIBILITIES Architecture, production, and reliability experience: Proven experience designing systems from scratch or significantly evolving existing architectures Experience working on production systems with real users Strong understanding of architectural trade-offs (performance, scalability, cost, and maintainability) Experience with monitoring, debugging, and performance optimization in production environments Familiarity with handling production issues and incidents Ownership and leadership: Experience owning major system components or leading technical decisions Ability to work independently with minimal supervision Experience mentoring junior or mid-level developers and collaborating within a team REQUIREMENTS At least 10 years of professional software development experience Proven experience working with SaaS-based systems Strong understanding of scalable systems and software architecture Hands-on experience with Node.js and React Excellent English proficiency and strong communication skills NICE TO HAVE Experience with cloud platforms such as AWS, GCP, or Azure Familiarity with CI/CD pipelines and modern DevOps practices Experience working in distributed or remote teams Product mindset — ability to understand business requirements and translate them into technical solution WHAT DO WE OFFER ON THIS PROJECT? Cooperation based on a B2B contract and rate: 24 000-27 000 PLN/hour 100% remote work The support of a dedicated mentor. In the relationship, we focus on direct communication. When you join speedapp, you will be put in touch with a dedicated mentor who will make sure that you enjoy working with us and with the client. Events and integration meetings, as well as participation in various initiatives, e.g., sports. Access to the benefits offering (medical care, life insurance, Multisport card). WHAT DOES THE RECRUITMENT PROCESS LOOK LIKE? Application: Apply and submit your CV. After the application review, the recruiter will contact selected candidates by phone. Screening: Have a conversation with a speedapp recruiter about your experience. Next steps: The speedapp recruiter will explain the recruitment process for the specific position. The speedapp recruiter will stay in touch with you throughout the entire process. ABOUT SPEEDAPP At speedapp, we believe that an organization is only as good as the people who make it up. We are a team of IT experts and other professionals working for our clients around the world (including Israel, Austria, USA). We go far beyond the HR category. We build IT teams and also help manage them. 👉 10 years of experience 👉 +100 clients worldwide +300 hires per year 💎 We have won the prestigious "Forbes Diamonds" award four times (2022, 2023, 2024, 2025). We are a member of the European Fast Growth Icons network and FinTech Poland. We are ranked 18th among the 100 fastest growing companies 2023 by Clutch. DO YOU HAVE ANY QUESTIONS? Contact the recruiter responsible for this process directly. Iga Olszewska-Magnowska Senior IT Delivery Consultant iga.olszewska@speedapp.pl

🏢 Summary: Full Stack Developer role focused on building scalable, cloud-native applications using React and C# .NET Core in a capital markets environment. The position involves developing microservices, REST APIs, data pipelines, and analytical solutions supporting credit and market risk domains. 100% remote B2B contract with flexible start date. 🗂️ Requirements: 4-5+ years of full stack development experience, Strong expertise in React, Strong expertise in C#, Experience with .NET Core, Experience with microservices architecture, Experience with event-driven architecture, Experience with distributed systems, Experience building REST APIs, Hands-on experience with Python, Experience with PySpark, Experience with Power BI, Experience with data modeling, Experience in credit risk and market risk domains 📃 Skills: React, C#, .NETCore, Microservices, REST, TypeScript, Python, PySpark, PowerBI, DataModeling, DistributedSystems, EventDriven, Cloud 🏢 Description: Start Date: ASAP / Within 1 Month / Flexible Work Model: 100% remote Contract Type: B2B (140-160 PLN/h + VAT) We are looking for a highly skilled Full Stack Developer with deep expertise in React for frontend development and C# .NET Core for backend services. This role requires hands‑on experience building scalable, cloud‑native systems, along with strong exposure to capital markets, especially within credit risk and market risk domains. Expectations Minimum 4-5 years of professional software development experience across frontend and backend technologies. Strong expertise in React, C# .NET Core , microservices, event‑driven architecture, and distributed systems. Hands‑on experience with Python (pyspark), Power BI dashboards, data modeling, and analytical reporting. Responsibilities Develop and maintain full stack applications using React, C# .NET Core, and modern cloud‑native technologies. Build scalable backend services, REST APIs, and microservices with a focus on performance and resilience. Implement modular, accessible, and high‑quality frontend components using React and TypeScript. Collaborate with business and risk experts to deliver solutions in credit risk, market risk, and capital markets workflows. Work with Python (pyspark) to build data pipelines, transformations, and analytics processes. What We Offer Medicover healthcare package Multisport card Access to an e-learning platform Group life insurance

🏢 Summary: Full-time Senior Full Stack Developer role focused on building scalable frontend applications and BFF services using TypeScript, React, Node.js, and NestJS. The position involves API and LLM integrations, frontend architecture design, performance optimization, and collaboration with product and engineering teams. Hybrid work from Kraków is expected 2–3 days per week. 🗂️ Requirements: Strong experience with TypeScript, Several years of software engineering experience, Strong React and modern frontend development expertise, Experience with frontend unit and integration testing, API design and development experience with NestJS, Experience with Node.js, Understanding of server-side rendering and Server Components, Knowledge of CDN strategies and caching, Understanding of software architecture and system design, Experience with Docker, Experience with Git, Experience with CI/CD, Experience with Azure, Ability to work in uncertain environments and solve problems pragmatically 📃 Skills: TypeScript, React, NestJS, Node.js, Docker, Git, CI/CD, Azure, GraphQL, Zustand, ReactQuery, Python 🏢 Description: Role overview Svitla Systems Inc. is looking for a Senior Full Stack Developer for a full-time position (40 hours per week) in Kraków, Poland. Our client is a British wholesale distributor. You will be responsible for building user interfaces with TypeScript and React, developing and maintaining BFF services, integrating APIs and LLM services, designing scalable frontend architecture, optimizing application performance and user experience, implementing error handling and resilience patterns, and collaborating with product and engineering teams to deliver features from prototype to production. Office work is expected 2-3 days per week. Responsibilities Building user interfaces using TypeScript and React. Building and maintaining Backend for Frontend (BFF) services to orchestrate API calls and shape data for user interface needs. Integrating APIs, LLM services, and streaming endpoints to deliver product features. Designing and implementing scalable and maintainable frontend architecture. Ensuring performance, responsiveness, and optimal user experience across the application. Implementing error handling, loading states, and resilience patterns for distributed systems. Collaborating with product and engineering teams to bring concepts from prototype to production. Requirements Strong hands-on experience with TypeScript development. Several years of experience in software engineering, ideally with a strong focus on React and modern frontend development tools. Experience with frontend testing, including unit and integration testing. API design and development experience using NestJS and Node.js. Understanding of server-side rendering, Server Components, CDN strategies, and caching. Solid understanding of software architecture, clean code, and system design. Ability to work effectively in environments with a high degree of uncertainty and take a pragmatic, solution-oriented approach to problem-solving. Experience with Docker, Git, CI/CD, and Azure. Nice to Have Knowledge of GraphQL APIs. Experience with state management libraries (e.g. Zustand, React Query). Familiarity with Python, particularly in the context of working with backend services or AI-powered systems. Experience building data-intensive or real-time user interfaces. Familiarity with designing user experiences for AI-powered features or non-deterministic outputs. We offer US and EU projects based on advanced technologies. Competitive compensation based on skills and experience. Regular performance appraisals to support your growth. Flexibility in the workspace, either remote or in our welcoming office. Comprehensive medical insurance after one month. MultiSport card with access to 2500 sports facilities all over Poland Bonuses for recommendations of new employees. Bonuses for article writing, public talks, and other activities. 15 vacation days, 10 national holidays, 10 sick leaves, and family days off. Personalized learning program tailored to your interests and skill development. Free tech webinars and meetups organized by Svitla. Welcome and anniversary presents, gifts for children, and more. Regular corporate events and meetups. Awesome team, friendly and supportive community!

🏢 Summary: Senior Full-Stack Developer role focused on enhancing and developing a modern web application across frontend and backend. The position involves implementing user stories, contributing to software architecture, and ensuring high code quality within an agile team. Remote B2B contract on an international project. 🗂️ Requirements: Several years of experience in Java development, Experience with Spring Boot or Jakarta EE or MicroProfile, Experience with modern frontend frameworks (Vue.js or React or Angular), Strong knowledge of frontend and backend web application development, Understanding of software architecture principles, Knowledge of clean code practices, Experience working in Scrum or Kanban environments 📃 Skills: Java, Spring, SpringBoot, JakartaEE, MicroProfile, Vue, React, Angular, HTML, CSS, JavaScript, Scrum, Kanban 🏢 Description: Summary: The role of a Senior Full-Stack Developer is essential for enhancing the functionality of a modern web application, contributing to both frontend and backend development to meet user requirements effectively. What we offer: Remote Role B2B Contract Big International project Rate: 42-45 euro/hour +VAT Main Responsibilities: Development and further enhancement of a modern web application in a full-stack environment. Implementation of functional requirements (user stories) within an agile team. Contribution to the design and further development of the software architecture. Ensuring code quality and maintainability. Close collaboration with other developers and business stakeholders. Key Requirements: Several years of professional experience in software development with Java (e.g. Spring Boot or Jakarta EE / MicroProfile). Experience with modern frontend frameworks (e.g. Vue.js, React, or Angular). Solid knowledge of web application development (frontend & backend). Understanding of software architecture and clean code principles. Experience working in agile teams (e.g. Scrum or Kanban). Self-driven and structured working style, as well as strong teamwork skills.