Senior Software Engineer

Overview The ADUEX Engineering organization is central to Mastercard’s growth strategy, delivering scalable, secure, and innovative solutions that empower small and medium businesses globally. Join a lean, high‑impact engineering team to build scalable cloud‑native software solutions from the ground up, solving complex technical problems at scale. This role is ideal for a Senior Software Engineer who thrives in complex environments, takes ownership of system design and quality, and consistently applies advanced engineering practices to ensure reliable, high performing, and secure systems. Role As a Senior Software Engineer, you will act as a technical owner and key contributor across the full software lifecycle, from architecture and design through production operations. Responsibilities Design and evolve scalable, maintainable, and secure software solutions, translating business and technical requirements into well‑structured system designs. Contribute to and influence architecture decisions, defining patterns, standards, and best practices for APIs, event‑driven systems, microservices, and cloud‑native platforms. Evaluate technical trade‑offs and guide design decisions that ensure long‑term system sustainability. Independently design, build, test, deploy, and maintain high‑quality software components and services. Apply advanced data structures and algorithms to solve complex problems efficiently and optimize system behavior. Lead and participate in code reviews, ensuring high standards for readability, maintainability, performance, and security. Coach and mentor peers through technical feedback, pairing, and informal guidance. Proactively analyze and optimize application and system performance, scalability, and reliability. Design and execute performance, load, and stress testing strategies; identify bottlenecks and drive tuning across application, data, and infrastructure layers. Define and maintain comprehensive unit, functional, and integration testing strategies; promote test automation and quality gates. Ensure systems behave predictably under normal and peak workloads. Design systems with operational readiness in mind, including observability, logging, monitoring, alerting, and resilience. Take ownership of production health within owned areas, participate in incident diagnosis, root‑cause analysis, and preventive improvements. Continuously improve reliability, maintainability, and supportability throughout the system lifecycle. Apply secure coding practices and adhere to Mastercard security standards and industry frameworks (e.g., OWASP, CWE). Ensure vulnerabilities are proactively identified and mitigated using automated tooling and secure design principles. Partner with Product, Architecture, Site Reliability, and Security teams to deliver aligned solutions; influence team decisions with data‑driven recommendations. Contribute to engineering communities, guilds, and knowledge‑sharing initiatives across Mastercard. All About You Proficiency in Python/TypeScript; hands‑on experience building agentic frameworks. Strong experience with modern web stacks, including Angular and React, and with JavaScript/TypeScript and Node.js / Java microservices. Proven backend development experience in Java; Spring Boot familiarity preferred. Solid understanding of data structures, algorithms, and performance optimization techniques. Hands‑on experience building and operating cloud‑native systems (AWS/Azure), including APIs, event‑driven services, and distributed data stores (SQL, key‑value, or document stores). Proven expertise in secure coding practices and use of static and dynamic security analysis tools (e.g., Sonar, Checkmarx). Strong experience with Git‑based workflows, branching strategies, and leading effective peer code reviews. Experience designing, implementing, and maintaining unit, service, and integration tests. Experience analyzing and troubleshooting issues across applications and production environments. Deep understanding of modern SDLC methodologies (Scrum, Kanban, SAFe) and when to apply them; experience with CI/CD pipelines, automation, and containerized deployments. Familiarity with observability tools and operational best practices for mission‑critical systems. Bachelor’s degree in Computer Science, Engineering, Information Technology, or equivalent practical experience (preferred). Roles, Locations, and Compensation Pay ranges: Arlington, Virginia: $132,000 - $212,000 USD; O'Fallon, Missouri: $115,000 - $184,000 USD. Mastercard is an inclusive, equal opportunity employer that considers applicants without regard to gender, gender identity, sexual orientation, race, ethnicity, disability, veteran status, or any other characteristic protected by law. Reasonable accommodations are available during the application process; please contact View email address on click.appcast.io to request accommodations. Corporate Security Responsibility All activities involving access to Mastercard assets, information, and networks come with inherent risk. All employees are responsible for information security and must: Abide by Mastercard’s security policies and practices; Ensure the confidentiality and integrity of information accessed; Report any suspected information security violation or breach; Complete all periodic mandatory security trainings in accordance with Mastercard’s guidelines. Note: This job description includes information about compensation and benefits that may vary by location and role and is intended for informational purposes. #J-18808-Ljbffr