Frontend Engineer (React, Typescript)

What you work on today shapes where you’ll be tomorrow. Looking for your next challenge as a Frontend Engineer ? 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 job: Advanced business logic on the frontend side - working with large data volumes, complex transformations, algorithmic operations and performance optimization; this is not a CRUD application - algorithmic correctness is a daily challenge Building and maintaining React components following the Atomic Design methodology, state management with Redux, integration with REST APIs and external desktop tools Ownership of software engineering - development is done after the business logic is recognized and mapped What you need to join us: Must have: React (advanced level) and TypeScript (advanced level) - hooks, Context API, performance optimization, typing of components, hooks, Redux actions and reducers, generic types Redux - deep understanding of the architecture and three core principles, react-redux integration via hooks (useSelector, useDispatch), state immutability, selector-based optimization Complex business logic implementation on the client side - asynchronous operations, REST API integration, architectural thinking about data flow, algorithmic performance with large datasets Atomic Design and MVC pattern - designing scalable and modular component structures, separation of logic from the view layer Engineering best practices - SOLID, unit/integration tests (mandatory code coverage), code reviews, Git, ownership of full epics and understanding business goals behind features English B2+ Ability to perform work in Poland (citizenship, residence permit, visa, etc.) Nice to have: Background extending beyond pure frontend (e.g., backend or systems-level programming experience) Experience or natural inclination for manual testing - finding edge cases and breaking applications (the team shares QA responsibilities) Experience with end-to-end testing frameworks Familiarity with embedding frontend UI as a panel within a desktop application