Full Stack Engineer

**Role: Full\-Stack Software Engineer** **Location: Stockholm, Sweden** **Type: Contract** **Job Description:** We are looking for an experienced Full\-Stack Engineer with deep expertise in modern JavaScript ecosystems, particularly Node.js and React. In this role, you will be responsible for designing, building, and maintaining scalable web applications from front\-end interfaces to backend services. You will collaborate closely with cross\-functional teams to deliver high\-quality, performant, and reliable products that serve a large user base. **Key Responsibilities** * Design, develop, and maintain end\-to\-end web applications using Node.js and React, ensuring high performance, responsiveness, and scalability. * Architect and implement robust backend services and APIs, including Backend\-for\-Frontend (BFF) layers tailored for different client applications (web and mobile). * Write clean, maintainable, and strongly typed code using TypeScript, following best practices and coding standards. * Lead system design discussions, contributing to decisions around scalability, caching strategies, performance optimization, and fault tolerance. * Build and optimize systems capable of handling high traffic and large\-scale production workloads. * Develop and maintain automated test suites, ensuring high code quality and reliability using tools such as Jest or Vitest. * Participate in code reviews, providing constructive feedback and ensuring adherence to engineering standards. * Collaborate with product managers, designers, and other stakeholders to translate business requirements into technical solutions. * Contribute to CI/CD pipelines, deployment processes, and operational excellence, including monitoring and observability. * Continuously identify areas for improvement in system architecture, development processes, and team practices. **Required skills:** * Strong hands\-on experience in full\-stack development, with deep expertise in Node.js and React. * Proficiency in TypeScript, with a track record of building scalable and maintainable codebases. * Solid understanding of Backend\-for\-Frontend (BFF) architecture and API design principles. * Experience with modern Node.js frameworks (experience with Fastify is a plus). * Strong grasp of system design fundamentals, including scalability, caching, performance tuning, and reliability. * Proven experience working on large\-scale, high\-traffic production systems. * Expertise in unit testing and automated testing frameworks such as Jest or Vitest. * Strong knowledge of software engineering best practices including clean code, testing strategies, CI/CD, and security considerations. * Experience working in Agile development environments, including sprint planning, estimation, and iterative delivery. * Excellent communication skills with the ability to collaborate effectively across technical and non\-technical teams.