Senior Software Engineer (MERN Stack & React Native)

**Company Description** Re is dedicated to building a sustainable and forward-thinking ecosystem, which we call the Re-verse. By focusing on awareness, materials, and energy, Re aims to reimagine and reshape humanity's relationship with the planet. We strive to innovate and drive change, creating a future where sustainability is at the core of every decision. Join us in rewriting the equation for a better tomorrow. **Role Description** We are looking for an experienced and highly capable Senior Software Engineer with 7+ years of professional software development experience to join our engineering team. In this role, you will take ownership of designing, developing, and scaling web and mobile applications across our product ecosystem. You will work closely with product managers, designers, and engineers to translate business requirements into robust, scalable, and intuitive technology solutions. The ideal candidate is someone who can operate independently, make sound technical decisions, mentor other engineers, and take ownership of features and products from concept through deployment and continuous improvement. **Responsibilities** * Lead the design, development, and maintenance of scalable web applications using the MERN Stack (MongoDB, Express.js, React.js, and Node.js). * Design, develop, and maintain production-grade React Native applications for iOS and Android. * Own features and technical initiatives end-to-end, from understanding requirements and architecture to development, testing, deployment, and maintenance. * Design scalable and maintainable application architectures and reusable components. * Build and integrate REST APIs and third-party services. * Develop responsive, high-performance, and intuitive user interfaces. * Work closely with product and design teams to translate business requirements into effective technical solutions. * Identify technical challenges and proactively propose scalable and practical solutions. * Review code and establish engineering best practices across the team. * Debug complex production issues and drive issues through to resolution. * Optimize application performance, reliability, scalability, and security. * Mentor junior and mid-level developers and contribute to their technical growth. * Participate in architecture discussions, technical planning, sprint planning, and product discussions. * Contribute to CI/CD, deployment, monitoring, and production release processes. * Stay up to date with modern technologies, frameworks, and software engineering practices. **Qualifications** * 7+ years of professional experience in software development. * Strong hands-on experience with JavaScript / TypeScript and modern development practices. * Strong expertise in React.js and frontend application architecture. * Strong experience with Node.js and Express.js. * Strong experience with MongoDB, including schema design, indexing, aggregation, and performance optimization. * Solid professional experience building and maintaining React Native applications. * Strong understanding of REST APIs, asynchronous programming, authentication, authorization, and third-party integrations. * Experience with state management solutions such as Redux / Redux Toolkit. * Strong understanding of Git and collaborative development workflows. * Experience with application performance optimization and debugging complex issues. * Understanding of software architecture, design patterns, scalability, and security best practices. * Experience working with cloud platforms, CI/CD pipelines, and production deployments. * Strong problem-solving and analytical abilities. * Excellent communication and collaboration skills. * Ability to take ownership, work independently, and make technical decisions with a product-first mindset. **Good to Have** * Strong TypeScript experience. * Experience with Firebase and cloud services. * Experience with AWS, Azure, or other cloud platforms. * Experience with Docker and CI/CD pipelines. * Experience with automated testing and test-driven development. * Experience with application monitoring and observability tools. * Experience working in an early-stage or high-growth startup environment. * Experience mentoring and leading engineering teams. * Exposure to AI-powered development tools and modern engineering workflows. **What You'll Gain** * Opportunity to build and scale real-world production web and mobile products. * Significant ownership and influence over technical and product decisions. * Opportunity to work on products focused on sustainability and meaningful global impact. * Collaboration with a multidisciplinary product, design, and engineering team. * Exposure to modern technologies, scalable architectures, cloud infrastructure, and production systems. * Opportunity to mentor engineers and contribute to building the engineering culture. * A fast-paced startup environment where your ideas and technical decisions can directly influence the product. * Opportunity for long-term growth and leadership within the organization.