Senior Software Engineer

Our Purpose Mastercard powers economies and empowers people in 200+ countries and territories worldwide. Together with our customers, we’re helping build a sustainable economy where everyone can prosper. We support a wide range of digital payments choices, making transactions secure, simple, smart and accessible. Our technology and innovation, partnerships and networks combine to deliver a unique set of products and services that help people, businesses and governments realize their greatest potential. Title and Summary Senior Software Engineer Overview We are looking for an experienced React.js + Node.js Developer with 6–7 years of hands-on experience in building scalable, high-performance web applications. The ideal candidate will have strong expertise in modern frontend and backend development, along with AI fluency and practical experience using AI-assisted development tools such as Claude and GitHub Copilot. The candidate should be comfortable using AI tools to improve developer productivity, accelerate development, generate and review code, troubleshoot issues, write tests, document solutions, and explore technical approaches—while maintaining strong engineering judgment and code quality.

Design, develop, and maintain scalable web applications using React.js and Node.js. Build reusable, maintainable, and high-performance React components. Develop robust backend services, RESTful APIs, and business logic using Node.js. Integrate frontend applications with backend APIs and third-party services. Design and work with SQL and NoSQL databases. Implement authentication, authorization, security, and data validation. Optimize application performance, scalability, and reliability. Write clean, modular, reusable, and well-documented code. Conduct code reviews and ensure adherence to engineering standards. Troubleshoot, debug, and resolve application and production issues. Collaborate with product managers, UI/UX designers, QA engineers, and other developers. Mentor junior developers and contribute to technical decision-making. Participate in Agile/Scrum ceremonies and technical discussions. AI Fluency & AI-Assisted Development: Demonstrate practical proficiency with AI coding assistants such as Claude and GitHub Copilot. Use AI tools effectively for: Code generation and refactoring. Debugging and root-cause analysis. Writing unit and integration tests. Generating technical documentation and code comments. Code reviews and identifying potential bugs or edge cases. Exploring alternative technical implementations and architectures. Automating repetitive development tasks. Demonstrate strong prompting skills and the ability to provide appropriate context, constraints, examples, and expected outcomes to AI tools. Validate, test, and review AI-generated code rather than relying on it blindly. Understand the limitations, security considerations, privacy concerns, and potential inaccuracies of AI-generated output. Stay current with emerging AI-assisted software development practices and developer productivity tools. Experience integrating AI capabilities or LLM-based APIs into applications is a strong plus. Required Technical Skills: Frontend 5+ years of strong experience with React.js. Excellent knowledge of JavaScript (ES6+) and TypeScript. Strong understanding of React Hooks, Context API, component lifecycle, and state management. Experience with Redux / Redux Toolkit or equivalent state-management solutions. Strong knowledge of HTML5, CSS3, responsive design, and modern UI development. Experience with frontend performance optimization. Familiarity with Jest, React Testing Library, or similar testing frameworks. Backend Strong hands-on experience with Node.js. Experience with Express.js, NestJS, or similar Node.js frameworks. Strong understanding of RESTful API development and integration. Experience with JWT, OAuth2, or similar authentication mechanisms. Good understanding of asynchronous programming and event-driven