Senior Fullstack Developer – React / Node.js

About the role

CLEEVEN, a European consulting company, is looking for a Senior Frontend-focused Fullstack Developer with strong expertise in React and Node.js. You will contribute to an enterprise conversational AI platform, improving its user experience, performance and integration with AI-powered services. The work focuses on improving an existing application, building reliable frontend and backend components and delivering secure, scalable solutions in the cloud.

Key responsibilities

• Develop and enhance a conversational web application using React, TypeScript and Node.js.
• Build reusable, responsive and accessible frontend components.
• Develop Node.js backend services and integrate external APIs.
• Connect the application with AI, search and knowledge-management services via REST APIs.
• Implement secure authentication and authorization (SSO, OIDC).
• Deploy and maintain containerized applications on AWS.
• Improve performance, security, reliability and monitoring.
• Develop automated tests and contribute to CI/CD pipelines.
• Collaborate with product owners, UX designers, architects and engineering teams.

Required profile

• Degree in Computer Science, Software Engineering or equivalent experience.
• Significant experience developing and maintaining enterprise web applications.
• Ability to improve existing applications while keeping code clean and scalable.
• Pragmatic, autonomous and solution-oriented; strong communication and teamwork skills.

Required skills

• React / ReactJS and modern frontend development
• Node.js for backend and API integration
• TypeScript and JavaScript
• REST APIs, authentication and system integration
• Enterprise authentication (SSO, OIDC)
• AWS, Docker and containerized deployments
• Git, CI/CD and modern software engineering practices
• Nice to have: conversational AI, Generative AI or RAG, AWS ECS/Fargate, Python-based AI services, monitoring/analytics dashboards, design systems and AI-assisted dev tools