Senior Full-Stack Engineer

This position is listed on behalf of a partner company, who manages all applications and next steps. Our partner is looking for a Senior Full-Stack Engineer based in Spain. As a Senior Full-Stack Engineer, you will play a key role in building and scaling a technology platform designed to deliver meaningful impact to users worldwide. This position combines backend engineering, frontend development, architecture, and product thinking to create reliable and scalable digital experiences. You will work across modern technologies, contribute to evolving system architecture, and help shape engineering practices within a collaborative remote environment. As a senior member of the team, you will influence technical direction while building solutions that balance performance, usability, and long-term maintainability. This is an opportunity to solve complex problems, leverage modern AI-assisted development practices, and contribute to products with a strong social purpose. Accountabilities Design, develop, and deliver end-to-end product features across backend services and modern frontend applications. Build scalable, maintainable backend services using technologies such as Java, Node.js, or similar modern development stacks. Create high-quality frontend experiences using React and TypeScript, focusing on usability, performance, and reusable components. Contribute to architectural decisions by defining system boundaries, improving domain models, and ensuring long-term platform scalability. Work effectively across a multi-stack production environment, improving existing systems while supporting ongoing platform evolution. Use AI-powered development tools to accelerate engineering workflows while reviewing, validating, and improving generated code before production deployment. Take ownership beyond feature development by contributing to CI/CD processes, cloud infrastructure, observability, reliability, and operational performance. Participate in code reviews, technical discussions, and knowledge-sharing activities to promote engineering excellence. Improve system security, stability, and maintainability through thoughtful technical decisions and continuous improvement. Requirements Strong professional experience in full-stack software engineering with proven backend and frontend development expertise. Solid experience with backend technologies such as Java, Node.js, or comparable modern programming environments. Strong frontend development skills with React, TypeScript, and modern web application practices. Deep understanding of software engineering fundamentals, including system design, data modelling, architecture patterns, and technical trade-offs. Experience working with production environments, including CI/CD pipelines, containerization, cloud platforms such as AWS, and application observability. Ability to work effectively with existing systems and evolve architecture incrementally rather than relying on large-scale rewrites. Experience using AI-assisted engineering tools as part of the development workflow while applying strong technical judgement and code review practices. Strong problem-solving skills with a pragmatic, product-focused approach to engineering decisions. Excellent communication skills and ability to collaborate effectively within remote, cross-functional teams. Ownership mindset with a focus on delivering sustainable value and improving engineering practices. Benefits Fully remote working environment with flexibility across Europe. Opportunity to contribute to a mission-driven product with meaningful global impact. Ability to influence technical direction and shape platform architecture as a senior engineer. Collaborative international team with colleagues across multiple countries and diverse backgrounds. Fast-growing environment with opportunities for professional development and career progression. Culture focused on ownership, continuous learning, feedback, and engineering excellence. Opportunity to work with modern technologies and AI-assisted development practices. Inclusive workplace that values diverse perspectives and encourages innovation. #J-18808-Ljbffr