Senior Frontend React Developer

O projekcie: Our Customer: Our client is a fast-growing cybersecurity technology company developing a large-scale platform for simulating cyberattacks and assessing security posture. The product includes complex web interfaces, high-load backend services, and cloud-native components. Wymagania: - 5+ years of professional experience in frontend or web development. - Senior-level expertise in React and the modern frontend ecosystem. - Excellent command of JavaScript, with a deep understanding of how the language works (execution context, async behavior, data handling). - Strong experience designing and maintaining reusable UI components and design systems (Storybook or similar). - Solid understanding of frontend application architecture, state management strategies, and data flow patterns. - Experience optimizing React applications for performance and scalability. - Working knowledge of backend integration (REST APIs, Node.js services). - Experience working with relational and/or NoSQL databases (e.g., PostgreSQL, MongoDB) at an integration level. - Familiarity with CI/CD pipelines and modern development workflows. - Strong focus on code quality, testing, and maintainability. - English — Upper-Intermediate+ (written and spoken). Codzienne zadania: - Design, develop, and maintain advanced frontend features using React and modern JavaScript (ES6+). - Build complex UI components, interactive dashboards, and scalable, reusable component libraries (including Storybook). - Own and evolve the frontend architecture, ensuring high performance, maintainability, and a consistent user experience across the platform. - Optimize rendering behavior and application performance, minimizing unnecessary re-renders and improving perceived UI responsiveness. - Collaborate closely with product managers, designers, and backend engineers to deliver high-quality features end to end. - Participate in technical discussions, frontend architecture decisions, and code reviews. - Integrate frontend applications with backend APIs (Node.js-based services). - Work with Git-based workflows and CI/CD pipelines to ensure smooth delivery and deployment. - Ensure clean, testable, and well-documented code following frontend best practices.