Senior Frontend Engineer

Senior Frontend Engineer Hybrid, Bucharest, Romania JOB OVERVIEW Legion is a high-performance, data-driven enterprise platform that supports complex forecasting, scheduling, and optimization capabilities. It also provides the services required by our web and mobile frontend applications. RESPONSIBILITIES AND DUTIES • As a Senior Frontend Software Engineer, you will be a member of the team responsible for the implementation and evolution of these applications. • You will need to be able to write secure, efficient, enterprise-quality code and have a deep understanding of the techniques and technologies necessary for scalability and performance. • Plan and conduct architecture sessions, design and build enhancements and extensions, and create plans for integration and unit testing. • Collaborate independently across frontend, backend, product, design, and quality engineering teams to resolve dependencies and make well-informed technical decisions. • Design and maintain highly available, reliable, and performant frontend applications that meet defined service-level agreements (SLAs) and service-level objectives (SLOs). • Manage difficult situations in a calm, structured, and timely manner. • Remain adaptable and prepared to respond effectively as priorities and requirements change. • Participate in Agile and Scrum ceremonies and contribute to planning, estimation, delivery, and continuous improvement. • Apply AI-assisted software development lifecycle (AI SDLC) practices across requirements, design, coding, testing, documentation, and automation to improve delivery velocity and quality. • Please note that this role involves active participation in an on-call rotation for critical support activities. REQUIRED SKILLS AND QUALIFICATIONS • 5–7 years of experience working with React and related frontend technologies. • Experience with React is essential. Experience with AngularJS and migrating AngularJS applications to React is preferred. • Strong experience with HTML5, CSS, JavaScript, TypeScript, and responsive, cross-browser frontend development. Familiarity with Bootstrap and jQuery is helpful when working with legacy applications. • Experience integrating frontend applications with REST APIs using modern state-management, data-fetching, caching, and error-handling patterns (e.g., Redux, Zustand, or TanStack), and writing automated frontend and end-to-end tests with Playwright. • Experience building software products and managing the complexities of multiple configurations in a cloud-based product, rather than consulting or webpage/portal development. • Bachelor’s or master’s degree in computer science, engineering, mathematics, or a similar field. PREFERRED QUALIFICATIONS AND ATTRIBUTES • Experience with mobile application development, including native iOS or Android applications; familiarity with React Native is a plus. • Our application runs on AWS, so experience with containerization and cloud deployments is preferred. • Familiarity with Java-based backend development and working with backend services and APIs is desirable. ABOUT LEGION Join Legion's mission to turn hourly jobs into good jobs. We're a mission-driven team seeking exceptional talent to propel this vision. Embrace a culture that's collaborative, fast-paced, and entrepreneurial. With us, you'll grow your skills, work closely with experienced executives, and contribute significantly to our mission. Our award-winning AI-native workforce management platform is intelligent, automated, and employee-centric and proven to deliver 13x ROI. We help labor-intensive organizations maximize labor efficiency and employee engagement simultaneously. Legion has earned recognition for its innovation, including spots on the Inc. 5000 list, Forbes’ Next Billio