Fullstack Engineer (Java/Kotlin + React) w Warszawa, Polska
Poland, Warszawa
Fullstack Engineer (Java/Kotlin + React) w Warszawa, Polska is listed on Jobeax. Browse 120,000+ vacancies available.
What you work on today shapes where you’ll be tomorrow.
Looking for your next challenge as a Fullstack Engineer (Java/Kotlin + React)? We may have the right opportunity for you.
At B3, we start with people and their experience. We match projects to your skills and professional growth path. Our consultants work across a wide range of industries and technologies, delivering IT projects both in Poland and internationally. This allows you to build your career in a deliberate way - not by chance.
We are part of an international organization listed on Nasdaq Stockholm, operating in 11 countries. In Poland, we operate with full autonomy. We choose our technologies, processes, and ways of working while maintaining the highest professional standards.
Join us today.
What we offer
Work in a Scandinavian culture built on logic, trust, and open dialogue.
Health and sports benefits tailored to your needs.
Speed Coaching – short sessions designed to provide new perspectives and solutions.
Sports training, an internal team, and opportunities to take part in competitions.
Key areas of the role:
Backend and APIs - Preparing mocks, designing and adjusting APIs in Java/Kotlin within a microservices architecture, enabling integrations with external strategic partners
Frontend in React - Building responsive web components, checkout funnels and registration paths, and integrating the frontend with the backend and the mobile app
Building new services the startup way - Working in a greenfield area on services that run outside the core market but are integrated with platform services (payments, login, search), delivering fast with the support of AI and agentic development tools
What you need to join us:
Must have:
Good programming skills in Java and/or Kotlin and confidence working with microservices
Hands-on frontend experience: HTML, CSS, JavaScript and modern frameworks (ideally React)
Clear understanding of REST API principles , working with JSON data and consuming backend endpoints
Ease of switching between backend and frontend, a problem-solver mindset , flexibility in a not-yet-defined area and exp. with with AI / agentic development tools
English at B2+ level or higher and Polish
Right to work in Poland (citizenship, residence card, visa, etc.)
Nice to have:
Familiarity with CI/CD tools (GitLab CI, Docker)
Experience with cloud environments
An eye for modern UX/UI standards, accessibility and Responsive Web Design (RWD)
Experience integrating with external systems and partners
Based in or near Warsaw or Poznań (occasional workshops and planning sessions in the office)
Senior Java Developer IT Factory, dynamiczna firma z doświadczeniem w zakresie rozwoju, wdrażania i wsparcia rozwiązań IT, dla polskiej znaczącej Firmy z branży ubezpieczeniowej, poszukuje Kandydatów/Kandydatek na stanowisko: Senior Java Developer Opis roli Osoba na tym stanowisku będzie odpowiedzialna za wytwarzanie kodu ...
Pełnienie roli Lidera Technicznego w projekcie rozwijanym w technologii Java/Spring. Projektowanie, rozwój i utrzymanie aplikacji backendowych opartych o Java oraz Spring Boot. Podejmowanie decyzji technicznych dotyczących architektury oraz jakości rozwijanego oprogramowania. Koordynowanie pracy zespołu programistów oraz ...
... bridging the gap between both — we'd love to hear from you. If you're an experienced developer looking for new challenges, diverse projects, and a supportive engineering culture, EPAM is the place to grow your career. Responsibilities Design, develop, and maintain scalable fullstack applications using Java-based backend technologies ...
... environments. Strong programming skills in Python and JavaScript/TypeScript, with experience in frameworks like FastAPI, Flask, https://jobeax.com/link/JSd7UYCSg572jJDY, React, Next.js. Working knowledge of LLMs, prompt engineering, fine-tuning, and retrieval-augmented generation (RAG). Experience connecting to GenAI APIs and managing ...
... and issues Deploy and monitor developed systems Requirements (fundamental): Minimum of 2 year of professional software development experience in Python or/and JavaScript, TypeScript, Java Bachelor’s degree in Computer Science or a related field or equivalent experience Proven experience in web apps (Angular, React or similar) ...
... enables corporate clients to manage liquidity, monitor payments and process transactions across borders in real time. We are looking for a skilled software engineer to join the product team that builds and evolves this critical platform. Resposibilities: Develop high-quality software that follows the multi-year product ...
... and issues Deploy and monitor developed systems Requirements (fundamental): Minimum of 2 year of professional software development experience in Python or/and JavaScript, TypeScript, Java Bachelor’s degree in Computer Science or a related field or equivalent experience Proven experience in web apps (Angular, React or similar) ...
Expected, Kotlin, AWS, Kubernetes, Microservices, PostgreSQL, Grafana, JUnit 5 About the project, Join a team working on a modern fintech platform that supports company expense management., , The project focuses on developing a finance solution that enables seamless integration of financial tools (including payment cards, ...
Astek Polska sp. z o.o. poszukuje Android Developera dla klienta z branży finansowej. Praca obejmuje rozwój i utrzymanie aplikacji mobilnych, wykorzystanie Kotlin Multiplatform, MVI, RxJava oraz Kotlin Coroutines. Wymagana jest dobra znajomość architektury Clean Architecture i Compose/Compose Multiplatform. Oferujemy długoterminową ...
... and secure WebView integrations connecting the app with partner systems What you need to join us: Must have: - Strong knowledge of the Android platform and Kotlin and/or Java, i ncluding the ability to build smooth, high-performance user interfaces - Extensive experience integrating remote B2B REST APIs in mobile applications ...
(B2B, employment contract, etc.). Hybrid work setup – 6 days a month from the office in Kraków, Flexible cooperation model – choose the form that suits you best
Praca hybrydowa
Elastyczne godziny
Tech stack: .NET Framework 4, WinForms / WPF, C#, https://jobeax.com/link/NY9VLwPeZTLjA7wT JavaScript, HTML, CSS, React SQL Server, PL-SQL Azure Requirements: Bachelor’s degree in Computer Science, Software Engineering, or a related technical field is a plus 4–5 years of commercial experience as a Software Engineer Strong ...
Tech stack: .NET Framework, .NET Core, .NET 6+, WinForms, WPF JavaScript, HTML, CSS, React SQL Server, Azure SQL Azure Requirements: Bachelor’s degree in Computer Science, Software Engineering, or a related technical field is a plus 4–5 years of commercial experience as a Software Engineer Strong knowledge of C# and the ...
... wkład w rozwój produktu poprzez dostarczanie rozwiązań technicznych i rekomendacji biznesowych., Realizacja zadań zgodnie z metodyką Scrum, na podstawie ustaleń z interesariuszami projektu., Projektowanie i rozwój mikroserwisów w technologii Java.] Requirements: Java, SQL, Spring, REST API, PostgreSQL, AWS
If you have the basics of Java down but feel the gap between "coding" and "building professional software," this 4-month program is your bridge. Designed by EPAM’s senior engineers, this training transforms your theoretical knowledge into the practical stack used on global projects. What you’ll master: We focus on the "Professional ...
Wymagane, Java, PostgreSQL, MongoDB, Spring Boot Mile widziane, Docker, GitHub Actions O projekcie, Wspólnie z naszym Partnerem z branży paliwowej poszukujemy doświadczonego/ej specjalisty/ki do świadczenia usług jako Java Developer., , Projekt obejmuje rozwój i utrzymanie aplikacji webowej do onboardingu klientów biznesowych ...
... Contribute to monitoring and observability using Prometheus, Grafana and the Elastic Stack Leverage AI-assisted development tools You bring: Computer Science/Engineering degree or equivalent background Minimum 3 years of commercial experience with Java and Spring Boot Experience with Docker and Kubernetes Experience with ...
... optimize performance Work with AI-driven development tools and AI agents Contribute to the platform's move to the cloud (AWS) You bring: 5+ years of commercial Java experience (Java 21, moving to Java 25) Familiarity with other languages such as C++ and Python Experience with Kafka, Gitlab and monitoring tools (Prometheus/SRE ...