Middle Fullstack developer for Lebara (, )

N-iX is looking for a talented Middle Fullstack engineer to join our team!

Our client is one of Europes fastest-growing mobile companies with over 5 million active customers 1000 employees worldwide and operations in five countries. The client is using the mobile virtual network operator business model.

We are seeking a skilled Full Stack Developer with expertise in and to design develop and maintain modern scalable web applications. The ideal candidate will have strong proficiency in both frontend and backend technologies experience in building performant applications and a good understanding of DevOps practices.

Responsibilities:

• Design develop and maintain scalable web applications using (React framework) and
• Build and optimize server-side rendering (SSR) and static site generation (SSG) with
• Develop and maintain RESTful APIs or GraphQL APIs using and related frameworks (Express etc.).
• Implement authentication authorization and secure data handling practices
• Collaborate with UI/UX designers to create responsive accessible and user-friendly interfaces
• Optimize application performance (caching code-splitting lazy loading CDN usage)
• Work with databases (SQL or NoSQL) for schema design queries and data modeling
• Integrate third-party services APIs and microservices
• Write clean maintainable and well-tested code
• Participate in code reviews design discussions and Agile/Scrum processes
• Deploy and monitor applications using cloud services (AWS GCP Azure) or platforms like Vercel

Requirements:

• 3 years of professional experience with and
• Strong experience in JavaScript (ES6) and TypeScript
• Hands-on experience with (SSR SSG API routes dynamic routing)
• Solid experience with and backend frameworks ( )
• Good understanding of React ecosystem (hooks context API state management libraries like Redux/Zustand)
• Experience with databases (PostgreSQL MySQL MongoDB or similar)
• Familiarity with RESTful APIs and GraphQL
• Knowledge of CI/CD pipelines Git and containerization (Docker/Kubernetes)
• Strong debugging and problem-solving skills
• Good understanding of web security best practices (JWT OAuth CSRF XSS etc.)

Would be a plus:

• Experience deploying applications on Vercel AWS Lambda or other serverless platforms
• Familiarity with Headless CMS (e.g. Strapi Sanity Contentful)
• Experience with testing frameworks (Jest Cypress Playwright)
• Knowledge of microservices and event-driven architectures
• Familiarity with WebSockets and real-time communication

Experience with performance optimization and SEO best practices for apps