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. Role 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 architecture. Experience with microservices is a plus. Database & Cloud Strong knowledge of PostgreSQL, MySQL, MongoDB, or similar databases. Experience with database design, queries, indexing, and performance optimization. Strong understanding of Git and Git-based development workflows. Experience with Docker and CI/CD pipelines. Exposure to AWS, Azure, or GCP. Understanding of application monitoring, logging, and deployment practices. Good to Have Strong TypeScript experience across frontend and backend. Experience with Next.js. Experience integrating LLM/Generative AI APIs into applications. Familiarity with AI concepts such as LLMs, prompt engineering, embeddings, RAG, vector databases, and AI agents. Experience with OpenAI, Anthropic, or other LLM APIs. Knowledge of Redis, Kafka, RabbitMQ, or similar technologies. Experience with Docker and Kubernetes. Understanding of system design and scalable architecture. Exposure to GraphQL. Experience working in an Agile/Scrum environment. Qualifications Bachelor's degree in Computer Science, Engineering, Information Technology, or a related field. 6–7 years of professional software development experience. Strong hands-on expertise in React.js and Node.js. Demonstrated ability to use AI-assisted development tools effectively and responsibly. Strong problem-solving and analytical skills. Excellent communication and collaboration skills. Ability to independently own features and deliver production-quality solutions. Preferred Candidate Profile The ideal candidate is a hands-on Senior Full Stack Developer who can work across the React.js frontend and Node.js backend and leverage modern AI tools to improve development efficiency. We are particularly interested in candidates who combine strong software engineering fundamentals with AI fluency—using tools such as Claude and GitHub Copilot as productivity multipliers while retaining ownership of architecture, code quality, security, testing, and technical decisions. Corporate Security Responsibility All activities involving access to Mastercard assets, information, and networks comes with an inherent risk to the organization and, therefore, it is expected that every person working for, or on behalf of, Mastercard is responsible for information security and must: Abide by Mastercard’s security policies and practices; Ensure the confidentiality and integrity of the information being accessed; Report any suspected information security violation or breach, and Complete all periodic mandatory security trainings in accordance with Mastercard’s guidelines.