Careers at Mastercard

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 At Mastercard Commercial Solutions, we empower businesses to succeed through innovative, trusted payment solutions that deliver seamless, digital-first experiences around the world. We are building a global business-to-business (B2B) technology platform that helps businesses of all sizes streamline how they manage payments when buying or selling products and services. The Mastercard Commercial Solutions team is looking for a Senior Software Engineer to advance our customer experience strategy through innovation and problem-solving. The ideal candidate is passionate about the customer journey and is highly motivated, intellectually curious, and analytical. Role You will work at our Mastercard technology location in O’Fallon, which provides a collaborative, state-of-the-art environment where technology teams can thrive within our Agile engineering culture. You will play a key role in transforming the B2B space by helping standardize, automate, and optimize digital payment efficiency for buyers and sellers. • Own software delivery activities at the application or software-component level, including design, development, testing, deployment, support, documentation, and configuration. • Develop full-stack solutions, including front-end applications, REST APIs, and backend services. • Translate business and technical requirements into scalable, secure, and maintainable software designs, defining appropriate components and system interactions. • Participate in Scrum ceremonies and contribute to continuous improvement using Agile methodologies. • Drive code, design, and process trade-off discussions within the team. • Promote the adoption of engineering principles, technology standards, and best practices. • Review code, testing, and automation produced by team members to ensure quality, security, standards compliance, and maintainability. • Develop a strong understanding of end-to-end technical architecture and system dependencies. • Evaluate application architecture and design decisions with consideration for scalability, performance, reliability, and long-term maintainability. • Mentor and guide new and less-experienced team members. • Develop and maintain unit, integration, functional, and regression tests. • Analyze and optimize application performance through testing, measurement, troubleshooting, and tuning. • Design and maintain applications for operational readiness by incorporating reliability, observability, monitoring, and effective production-support practices. • Troubleshoot production incidents and implement corrective and preventive actions. • Share and seek knowledge within the Guild and program to promote the reuse of patterns, libraries, and engineering practices. All About You Required Experience • Experience developing secure full-stack applications using backend and front-end technologies such as Java, JavaScript, Angular, and SQL. • Strong knowledge of Spring, Spring Data JPA, REST APIs, Kafka, and related frameworks. • Experience designing, implementing, and maintaining unit, service, integration, functional, and regression tests using tools such as JUnit, Mockito, and Jasmine. • Knowledge of application and design patterns used to implement APIs, event-driven services, batch services, and user-interface applications. • Strong understanding of data structures and their application in building efficient, reliable, and maintainable software. • Experience applying secure coding standards and vulnerability-management practices throughout the software development lifecycle. • Experience implementing API standards and cataloging practices to support service adoption, reuse, and commercialization. • Experience using tools such as Sonar, CxOne, Checkmarx, Black Duck, and Zally to evaluate code quality, security vulnerabilities, and anti-patterns. • Experience orchestrating release workflows and implementing standardized continuous integration and continuous delivery pipelines using tools such as Jenkins and XL Release. • Experience evaluating and improving application performance, scalability, and reliability using appropriate testing and tuning techniques. • Strong problem-solving and creative troubleshooting skills, with the ability to diagnose and resolve issues across applications and integrated systems. • Strong organizational skills and the ability to manage multiple priorities within business timelines. • Self-motivated and proactive, with a commitment to continuous improvement and delivering results. • Ability to thrive in a fast-paced, rapidly changing, and customer-focused environment. • Ability to promote full-stack engineering practices and end-to-end service ownership across teams. • Strong written and verbal communication skills. • Bachelor’s degree in Computer Science, Software Engineering, or a related field. • Eight or more years of relevant software engineering or information technology experience. Desirable Skills • Experience with monitoring and observability tools such as Splunk or Dynatrace. Mastercard is a merit-based, inclusive, equal opportunity employer that considers applicants without regard to gender, gender identity, sexual orientation, race, ethnicity, disabled or veteran status, or any other characteristic protected by law. We hire the most qualified candidate for the role. In the US or Canada, if you require accommodations or assistance to complete the online application process or during the recruitment process, please contact reasonable_accommodation@mastercard.com and identify the type of accommodation or assistance you are requesting. Do not include any medical or health information in this email. The Reasonable Accommodations team will respond to your email promptly. 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. In line with Mastercard’s total compensation philosophy and assuming that the job will be performed in the US, the successful candidate will be offered a competitive base salary and may be eligible for an annual bonus or commissions depending on the role. The base salary offered may vary depending on multiple factors, including but not limited to location, job-related knowledge, skills, and experience. Mastercard benefits for full time (and certain part time) employees generally include: insurance (including medical, prescription drug, dental, vision, disability, life insurance); flexible spending account and health savings account; paid leaves (including 16 weeks of new parent leave and up to 20 days of bereavement leave); 80 hours of Paid Sick and Safe Time, 25 days of vacation time and 5 personal days, pro-rated based on date of hire; 10 annual paid U.S. observed holidays; 401k with a best-in-class company match; deferred compensation for eligible roles; fitness reimbursement or on-site fitness facilities; eligibility for tuition reimbursement; and many more. Mastercard benefits for interns generally include: 56 hours of Paid Sick and Safe Time; jury duty leave; and on-site fitness facilities in some locations. THIS POSTING RELECTS ONE OR MORE CURRENT VACANCIES ON OUR TEAM, AND MASTERCARD INTENDS TO FILL THIS POSITION BY 12/27/2026. Pay Ranges O'Fallon, Missouri: $115,000 - $184,000 USD

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 Who is Mastercard? We work to connect and power an inclusive, digital economy that benefits everyone, everywhere, by making transactions safe, simple, smart, and accessible. Using secure data and networks, partnerships, and passion, our innovations and solutions help individuals, financial institutions, governments, and businesses realize their greatest potential. Our decency quotient, or DQ, drives our culture and everything we do inside and outside of our company. We cultivate a culture of inclusion for all employees that respect their individual strengths, views, and experiences. We believe that our differences enable us to be a better team – one that makes better decisions, drives innovation, and delivers better business results About the Role Senior Software Engineers at Mastercard design and code artificial intelligence, cloud, and machine learning platforms that provide mission-critical insights to many of the world’s leading organizations and governments. As a Senior Software Engineer, you will deliver these products and solutions with speed and agility as part of a small team. This will involve developing high-performing, highly scalable software solutions and products for some of the world’s top brands. Specific tasks vary depending on the project and the business unit that you join in. Role As a Senior Software Engineer, you will: Software Engineering & Development • Design, build, test, deploy, and maintain software components, automation frameworks, and validation tools • Apply strong knowledge of data structures, algorithms, and efficient coding practices in building scalable solutions • Contribute to end-to-end software development lifecycle, including design, development, testing, deployment, and monitoring Architecture & Design • Participate in defining software architecture and design patterns to ensure scalability, reliability, and maintainability • Ensure systems are designed for testability, observability, performance, and operational readiness • Provide input into microservices and cloud migration strategies Quality Engineering & Testing • Develop and implement test automation frameworks and CI/CD integration pipelines (e.g., Jenkins, XLR) • Design comprehensive test strategies and plans, including performance, reliability, and production simulation testing • Ensure high code quality and coverage using tools such as Sonar or Clover Security & Compliance • Apply and promote secure coding practices, including code analysis, vulnerability detection, and mitigation strategies • Integrate security testing into CI/CD pipelines Code Quality & Reviews • Conduct and lead code reviews, ensuring adherence to coding standards, security practices, and maintainability • Act as a technical reviewer for system designs, test strategies, and implementation approaches Operability & Performance • Ensure systems are observable, monitorable, and resilient across environments • Perform performance engineering, including load testing, tuning, and bottleneck analysis • Troubleshoot complex production issues and ensure rapid resolution Collaboration & Leadership • Partner with developers, architects, and product teams to drive engineering best practices • Mentor junior engineers and contribute to knowledge sharing across teams • Evaluate and recommend tools, technologies, and frameworks for continuous improvement All About You • Demonstrated experience developing microservices with JAVA and Spring Boot, required • Proven skills working with relational SQL database, preferably PostgreSQL and Oracle SQL • Advanced understanding of cloud native architecture, PCF, and AWS • Clear proficiency with engineering principles used in building and running mission critical software capabilities (security, scalability, resiliency, customer experience, testing, operability, simplification) • Apply tools (e.g., Sonar, Zally, Checkmarx) and techniques to scan and measure code quality and anti-patterns as part of development activity • Ability to perform domain-driven design to architect and map software solutions to business contexts • Proficient in orchestrating release workflows and pipelines, and apply standardized pipelines via APIs to achieve CI and CD using industry standard tools (e.g., Jenkins, AWS, XL Release, others); • Ability to configure rules and build automation for code with vulnerability scanning and software composition analysis using standard tools (e.g., Sonar, JFrog, XRay, Veracode, others) • Manage builds and artifacts leveraging standard tools (e.g., Artifactory) to ensure error-free deployment of production code using canary and/or blue-green techniques • Ability to work on relational data concepts, preferably with PostgreSQL databases. • Strong analytical and problem-solving skills, with the ability to debug issues and identify practical solutions. • Strong verbal and written communication skills and the ability to work effectively in a collaborative team environment. • Strong hands-on experience in software engineering, including development and quality engineering • Proven experience working with: • Testing across platforms: Linux and web applications • Automation development and CI/CD integration and deployment (Jenkins / XLR/ GitHub Actions) and code coverage tools (Sonar, Clover) to ensure high code/ conditional coverage • Unit, functional, and integration testing • Performance testing and engineering • Strong knowledge and understanding of: • Software design principles (OOP, modularity, design patterns) • Software architecture concepts (microservices, distributed systems, scalability) • Data structures and algorithms • Experience with secure coding practices and application security principles (e.g., OWASP) • Ability to contribute to system design and architecture decisions; understanding use cases for advanced design patterns (e.g., service-to-worker, MVC, API Gateway, Intercepting Filter, Dependency Injection, Lazy Loading, all from the gang of four) to implement efficient code Preferred Qualifications • Experience in cloud and microservices architecture or mainframe modernization • Experience designing systems for reliability, performance, and scalability • Domain knowledge in payments and transaction processing systems • Bachelor’s or master's degree in computer science or equivalent experience is preferred Mastercard is a merit-based, inclusive, equal opportunity employer that considers applicants without regard to gender, gender identity, sexual orientation, race, ethnicity, disabled or veteran status, or any other characteristic protected by law. We hire the most qualified candidate for the role. In the US or Canada, if you require accommodations or assistance to complete the online application process or during the recruitment process, please contact reasonable_accommodation@mastercard.com and identify the type of accommodation or assistance you are requesting. Do not include any medical or health information in this email. The Reasonable Accommodations team will respond to your email promptly. 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. In line with Mastercard’s total compensation philosophy and assuming that the job will be performed in the US, the successful candidate will be offered a competitive base salary and may be eligible for an annual bonus or commissions depending on the role. The base salary offered may vary depending on multiple factors, including but not limited to location, job-related knowledge, skills, and experience. Mastercard benefits for full time (and certain part time) employees generally include: insurance (including medical, prescription drug, dental, vision, disability, life insurance); flexible spending account and health savings account; paid leaves (including 16 weeks of new parent leave and up to 20 days of bereavement leave); 80 hours of Paid Sick and Safe Time, 25 days of vacation time and 5 personal days, pro-rated based on date of hire; 10 annual paid U.S. observed holidays; 401k with a best-in-class company match; deferred compensation for eligible roles; fitness reimbursement or on-site fitness facilities; eligibility for tuition reimbursement; and many more. Mastercard benefits for interns generally include: 56 hours of Paid Sick and Safe Time; jury duty leave; and on-site fitness facilities in some locations. THIS POSTING RELECTS ONE OR MORE CURRENT VACANCIES ON OUR TEAM, AND MASTERCARD INTENDS TO FILL THIS POSITION BY 12/17/2026. Pay Ranges O'Fallon, Missouri: $115,000 - $184,000 USD

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 The ABU team enables issuers and acquirers to securely communicate account changes for credential-on-file and recurring payments to merchants. This helps increase approval rates for card-not-present transactions, improve customer satisfaction, and reduce customer service demand. We continue to strengthen platform performance, resiliency, and scalability to support evolving on-soil regulations and growing global demand. We are modernizing the ABU platform and looking for a Senior Software Engineer to build and enhance highly available, distributed systems. This role provides the opportunity to solve complex technical challenges, contribute to architectural decisions, and deliver secure, reliable software at scale. Role -Design, develop, and maintain Java-based backend services using Spring Boot, Spring Integration, gRPC, and distributed system patterns. -Translate business requirements and user stories into secure, efficient, and reusable software solutions. -Contribute to technical design and architecture decisions that support performance, resiliency, maintainability, and system functionality. -Create and maintain automated unit, functional, and integration tests to validate quality and interoperability. -Analyze application performance, identify bottlenecks, and implement optimized solutions that meet service-level objectives. -Apply secure coding practices and established engineering standards throughout the software development lifecycle. -Conduct code reviews focused on quality, maintainability, and technical standards while mentoring junior team members. -Troubleshoot complex issues across distributed systems, complete root-cause analysis, and implement lasting fixes. -Support operational readiness through monitoring, observability, recoverability, and production support practices. -Manage individual priorities, deadlines, user stories, and deliverables. -Participate in Agile ceremonies, including daily stand-ups, story refinement, estimation, sprint planning, and retrospectives. -Partner across Engineering, Architecture, Product Management, Testing, Release Management, and Application Support to deliver quality solutions. All About You -Bachelor’s degree in Computer Science, Software Engineering, or a related technical field preferred. -Strong backend engineering background with Java, Spring Boot, Spring Integration, and REST or SOAP services. -Proven ability to design, develop, test, and support enterprise-scale applications. -Knowledge of software design principles, architectural patterns, domain-driven design, and non-functional requirements. -Ability to interpret user stories and technical requirements and translate them into simple, scalable, and maintainable features. -Advanced understanding of object-oriented programming, data structures, and algorithms. -Experience creating automated unit, functional, and integration tests within continuous integration environments. -Experience with messaging, event-driven architectures, and distributed communication technologies such as Apache Kafka or gRPC. -Proficiency with Oracle and SQL databases. -Knowledge of cloud-native development using AWS, Pivotal Cloud Foundry, or similar platforms. -Familiarity with automated build, deployment, and continuous integration systems. -Experience with tools such as Jenkins, Bitbucket, Artifactory, GitHub, and the Atlassian suite. -Ability to assess system performance and implement solutions that improve efficiency, scalability, and reliability. -Strong troubleshooting and root-cause analysis skills across distributed applications. -Understanding of secure coding, vulnerability prevention, and software security standards. -Experience supporting production systems through monitoring, observability, recoverability, and operational readiness practices. -Preferred experience using AI-assisted software development tools such as GitHub Copilot or Claude Code. -Effective written and verbal communication skills with the ability to build collaborative cross-functional partnerships. -Ability to work independently in complex environments while providing technical guidance through code reviews, mentorship, and knowledge sharing. Mastercard is a merit-based, inclusive, equal opportunity employer that considers applicants without regard to gender, gender identity, sexual orientation, race, ethnicity, disabled or veteran status, or any other characteristic protected by law. We hire the most qualified candidate for the role. In the US or Canada, if you require accommodations or assistance to complete the online application process or during the recruitment process, please contact reasonable_accommodation@mastercard.com and identify the type of accommodation or assistance you are requesting. Do not include any medical or health information in this email. The Reasonable Accommodations team will respond to your email promptly. 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. In line with Mastercard’s total compensation philosophy and assuming that the job will be performed in the US, the successful candidate will be offered a competitive base salary and may be eligible for an annual bonus or commissions depending on the role. The base salary offered may vary depending on multiple factors, including but not limited to location, job-related knowledge, skills, and experience. Mastercard benefits for full time (and certain part time) employees generally include: insurance (including medical, prescription drug, dental, vision, disability, life insurance); flexible spending account and health savings account; paid leaves (including 16 weeks of new parent leave and up to 20 days of bereavement leave); 80 hours of Paid Sick and Safe Time, 25 days of vacation time and 5 personal days, pro-rated based on date of hire; 10 annual paid U.S. observed holidays; 401k with a best-in-class company match; deferred compensation for eligible roles; fitness reimbursement or on-site fitness facilities; eligibility for tuition reimbursement; and many more. Mastercard benefits for interns generally include: 56 hours of Paid Sick and Safe Time; jury duty leave; and on-site fitness facilities in some locations. THIS POSTING RELECTS ONE OR MORE CURRENT VACANCIES ON OUR TEAM, AND MASTERCARD INTENDS TO FILL THIS POSITION BY 12/13/2026. Pay Ranges O'Fallon, Missouri: $115,000 - $184,000 USD

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 AI Engineer, Big Data & AI Solutions Overview The Security Solutions Data Science team develops AI and machine learning capabilities that help protect the global payments ecosystem from fraud and cyber threats. Supporting Mastercard's Safety Net product, the team creates and enhances models that analyze billions of transactions and identify suspicious activity in real time. As a Senior AI Engineer, you will work at the intersection of AI engineering and big data engineering, helping improve the models, data assets, and operational processes that power fraud detection. You will collaborate closely with Data Scientists and Engineers to strengthen feature engineering, advance model monitoring capabilities, and deliver AI-driven solutions that improve performance and efficiency. Role As a Senior AI Engineer, you will: -Support machine learning models that help detect cyber-attacks, fraud and improve decision intelligence. -Create data pipelines and feature engineering workflows that enable model development and evaluation. -Process and analyze large-scale datasets to uncover insights and improve model inputs. -Strengthen monitoring, observability, and drift detection capabilities across production environments. -Apply automation and MLOps practices to improve reliability, efficiency, and scalability. -Develop AI-powered solutions that address engineering challenges and streamline operational processes. -Partner with Data Scientists, Engineers, and Product teams to bring new capabilities into production. -Contribute ideas that improve model performance, operational visibility, and team productivity. Required Qualifications -Master’s degree with 2+ years of relevant experience, or Bachelor’s degree with 5+ years of relevant experience, in Computer Science, Artificial Intelligence, Machine Learning, Data Science, Engineering, or a related field; equivalent practical experience will also be considered. -Proficiency in Python, PySpark, SQL, and distributed data processing. -Hands-on experience with feature engineering, large-scale data processing, and analytics. -Hands-on experience with Databricks, Airflow, Hadoop, Linux/Unix, cloud-native technologies -Understanding of machine learning and deep learning techniques. -Understanding of model deployment, evaluation, monitoring, and optimization. -Knowledge of MLOps concepts including testing, automation, CI/CD, and version control. -Ability to communicate technical concepts and collaborate across teams. Preferred Qualifications -Fraud, cybersecurity, payments, or risk management domains. -Experience with Generative AI, LLMs, RAG, or agentic AI applications. -Familiar with AI-assisted development tools such as GitHub Copilot, or Claude Code. -Experience working with cloud-based data and AI environments. Mastercard is a merit-based, inclusive, equal opportunity employer that considers applicants without regard to gender, gender identity, sexual orientation, race, ethnicity, disabled or veteran status, or any other characteristic protected by law. We hire the most qualified candidate for the role. In the US or Canada, if you require accommodations or assistance to complete the online application process or during the recruitment process, please contact reasonable_accommodation@mastercard.com and identify the type of accommodation or assistance you are requesting. Do not include any medical or health information in this email. The Reasonable Accommodations team will respond to your email promptly. 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. In line with Mastercard’s total compensation philosophy and assuming that the job will be performed in the US, the successful candidate will be offered a competitive base salary and may be eligible for an annual bonus or commissions depending on the role. The base salary offered may vary depending on multiple factors, including but not limited to location, job-related knowledge, skills, and experience. Mastercard benefits for full time (and certain part time) employees generally include: insurance (including medical, prescription drug, dental, vision, disability, life insurance); flexible spending account and health savings account; paid leaves (including 16 weeks of new parent leave and up to 20 days of bereavement leave); 80 hours of Paid Sick and Safe Time, 25 days of vacation time and 5 personal days, pro-rated based on date of hire; 10 annual paid U.S. observed holidays; 401k with a best-in-class company match; deferred compensation for eligible roles; fitness reimbursement or on-site fitness facilities; eligibility for tuition reimbursement; and many more. Mastercard benefits for interns generally include: 56 hours of Paid Sick and Safe Time; jury duty leave; and on-site fitness facilities in some locations. THIS POSTING RELECTS ONE OR MORE CURRENT VACANCIES ON OUR TEAM, AND MASTERCARD INTENDS TO FILL THIS POSITION BY 11/12/2026. Pay Ranges O'Fallon, Missouri: $115,000 - $184,000 USD

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 Mastercard's Core Payments engineering teams build and support the platforms responsible for secure, reliable, and scalable payment capabilities around the world. This Senior Full Stack Software Engineer will contribute to mission-critical solutions that support Foreign Exchange rate setting across Mastercard, including external APIs clients use to access exchange rates and internal services that help power high-impact payment operations. Working closely with product managers, business stakeholders, and engineering teams, you will design and deliver new features, strengthen automated testing practices, and improve the efficiency, quality, and stability of systems operating at global scale. This role is well suited for a software engineer who can move across front-end, back-end, APIs, and automated integration testing while staying curious, collaborative, and quick to respond when something breaks during development. Role •Design, develop, and enhance full stack applications, APIs, and services that support Mastercard's Core Payments and Foreign Exchange rate-setting capabilities. •Deliver new features from design sessions and team planning through implementation, automated testing, release support, and ongoing enhancement. •Build and maintain automated unit, functional, integration, and regression tests that improve release speed and help the team quickly identify issues during development. •Support work that is approximately 10% design sessions and team meetings, 60% software implementation, and 30% automated integration testing and development. •Build business and product knowledge over time, becoming a trusted resource within the team while helping newer engineers learn, ask questions, and grow. •Translate business and product requirements into scalable, maintainable solutions that meet functional and non-functional requirements. •Define acceptance criteria, testing strategies, and quality standards that promote stable and predictable releases. •Participate in requirements reviews, sprint planning, and technical discussions to deliver incremental value throughout the development lifecycle. •Create and maintain technical designs, user stories, and test cases using Jira. •Contribute to architecture discussions, helping shape solutions that prioritize performance, resiliency, maintainability, and security. •Review code, provide constructive feedback, and promote engineering practices that improve software quality and reduce technical debt. •Analyze system behavior, troubleshoot production issues, perform root-cause analysis, and implement long-term corrective actions. •Enhance operational readiness through monitoring, observability, recoverability, and supportability improvements. •Identify opportunities to optimize application performance and scalability while supporting service-level objectives. All About You •Strong proficiency in Java, Spring Boot, Jakarta Persistence API/JPA, and REST-based services using JSON and XML. •Proven ability to build automated unit, functional, integration, and regression testing solutions, with a clear understanding of why automation matters for mission-critical systems. •Ability to work across APIs, web applications, and full stack development, with Angular or a similar front-end framework strongly preferred; React is also relevant. •Curious, humble, and open to new ideas, with the confidence to ask questions, learn quickly, and support a collaborative team environment. •Ability to design scalable software solutions that balance performance, maintainability, security, and operational reliability. •Familiarity with distributed systems, service-oriented architectures, and modern software design patterns. •Strong understanding of software quality principles, test strategy development, and automation frameworks such as JUnit. •Knowledge of CI/CD practices and automated delivery pipelines. •Ability to evaluate code quality, identify improvement opportunities, and contribute to a culture of continuous improvement. •Strong troubleshooting and analytical skills with the ability to diagnose and resolve complex technical issues. •Understanding of performance engineering concepts, including scalability, throughput, and optimization techniques. •Commitment to secure coding practices and development standards that support highly available enterprise applications. •Solid understanding of data structures and algorithms and their application to real-world engineering challenges. •Effective communication skills with the ability to collaborate across engineering, product, program management, and business teams. •Comfortable balancing multiple priorities while delivering high-quality solutions in a fast-paced Agile environment. •Familiarity with Agile methodologies and tools such as Jira. Mastercard is a merit-based, inclusive, equal opportunity employer that considers applicants without regard to gender, gender identity, sexual orientation, race, ethnicity, disabled or veteran status, or any other characteristic protected by law. We hire the most qualified candidate for the role. In the US or Canada, if you require accommodations or assistance to complete the online application process or during the recruitment process, please contact reasonable_accommodation@mastercard.com and identify the type of accommodation or assistance you are requesting. Do not include any medical or health information in this email. The Reasonable Accommodations team will respond to your email promptly. 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. In line with Mastercard’s total compensation philosophy and assuming that the job will be performed in the US, the successful candidate will be offered a competitive base salary and may be eligible for an annual bonus or commissions depending on the role. The base salary offered may vary depending on multiple factors, including but not limited to location, job-related knowledge, skills, and experience. Mastercard benefits for full time (and certain part time) employees generally include: insurance (including medical, prescription drug, dental, vision, disability, life insurance); flexible spending account and health savings account; paid leaves (including 16 weeks of new parent leave and up to 20 days of bereavement leave); 80 hours of Paid Sick and Safe Time, 25 days of vacation time and 5 personal days, pro-rated based on date of hire; 10 annual paid U.S. observed holidays; 401k with a best-in-class company match; deferred compensation for eligible roles; fitness reimbursement or on-site fitness facilities; eligibility for tuition reimbursement; and many more. Mastercard benefits for interns generally include: 56 hours of Paid Sick and Safe Time; jury duty leave; and on-site fitness facilities in some locations. THIS POSTING RELECTS ONE OR MORE CURRENT VACANCIES ON OUR TEAM, AND MASTERCARD INTENDS TO FILL THIS POSITION BY 12/09/2026. Pay Ranges O'Fallon, Missouri: $115,000 - $184,000 USD

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 Next Edge represents the next phase of Mastercard's Core Payments technology transformation and plays a key role in advancing our cloud-first strategy. This organization is focused on modernizing payment platforms, creating scalable engineering solutions, and delivering the tools and services that enable teams to build, test, and deploy software more efficiently. As a Senior Software Engineer, you will contribute to the design and development of internal platforms, backend services, and engineering tools that improve developer productivity and accelerate delivery across Mastercard's payment ecosystem. Working closely with engineers, product managers, designers, and technical leads, you will help build reliable, scalable solutions while driving continuous improvements in software quality, performance, and maintainability. This role is ideal for an engineer who enjoys solving complex technical challenges, building modern distributed systems, and working with evolving technologies that support innovation at enterprise scale. Role -Design, develop, and support internal platforms, microservices, and engineering tools that improve productivity and accelerate software delivery. -Partner with technical leads and team members to scope, design, and implement complex features from concept through production deployment. -Build high-quality, maintainable code and automated tests that contribute to reliable and efficient software delivery. -Develop backend services and supporting tools using technologies such as Golang, Java, and gRPC. -Contribute to software architecture and design decisions that improve scalability, resiliency, maintainability, and operational readiness. -Collaborate with Product Managers and Customer Experience Designers to understand user needs and translate requirements into technical solutions. -Review code, share feedback, and promote engineering practices that enhance quality, readability, security, and long-term maintainability. -Analyze system behavior, troubleshoot complex issues, identify root causes, and implement sustainable solutions. -Improve application performance, reliability, and observability across services and platforms. -Contribute to automation initiatives, development workflows, and engineering practices that increase team effectiveness and delivery speed. -Support and guide less experienced engineers through knowledge sharing, technical discussions, and collaborative problem solving. -Stay current with emerging technologies and evaluate opportunities to apply them where they create measurable value. All About You -Strong proficiency in Golang, Java, or comparable object-oriented programming languages. -Ability to design and implement complex features within large-scale applications and distributed systems. -Familiarity with microservices architecture, service-to-service communication patterns, and API development. -Understanding of software design principles and architectural patterns that support scalable, resilient applications. -Capability to write clean, maintainable code while balancing performance, reliability, and long-term sustainability. -Proven success contributing to large engineering initiatives involving multiple teams and stakeholders. -Strong foundation in data structures, algorithms, and problem-solving techniques. -Ability to evaluate and optimize application performance in high-volume, transaction-oriented environments. -Commitment to automated testing, code quality, and continuous improvement throughout the software development lifecycle. -Familiarity with secure coding practices and modern software engineering standards. -Strong troubleshooting skills with the ability to diagnose and resolve issues across complex systems. -Comfortable working within Agile environments and collaborating with -geographically distributed teams. -Customer-focused mindset with an appreciation for how technical decisions influence user outcomes. -Curiosity and willingness to learn new technologies, frameworks, and development approaches. -Effective communication skills with the ability to collaborate across engineering, product, and design teams. -Degree in Computer Science, Engineering, or a related technical discipline, or equivalent practical background. -AI-first mindset with the ability to leverage tools such as GitHub Copilot, Claude Code, ChatGPT, and similar technologies to improve productivity, code quality, and delivery outcomes. Mastercard is a merit-based, inclusive, equal opportunity employer that considers applicants without regard to gender, gender identity, sexual orientation, race, ethnicity, disabled or veteran status, or any other characteristic protected by law. We hire the most qualified candidate for the role. In the US or Canada, if you require accommodations or assistance to complete the online application process or during the recruitment process, please contact reasonable_accommodation@mastercard.com and identify the type of accommodation or assistance you are requesting. Do not include any medical or health information in this email. The Reasonable Accommodations team will respond to your email promptly. 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. In line with Mastercard’s total compensation philosophy and assuming that the job will be performed in the US, the successful candidate will be offered a competitive base salary and may be eligible for an annual bonus or commissions depending on the role. The base salary offered may vary depending on multiple factors, including but not limited to location, job-related knowledge, skills, and experience. Mastercard benefits for full time (and certain part time) employees generally include: insurance (including medical, prescription drug, dental, vision, disability, life insurance); flexible spending account and health savings account; paid leaves (including 16 weeks of new parent leave and up to 20 days of bereavement leave); 80 hours of Paid Sick and Safe Time, 25 days of vacation time and 5 personal days, pro-rated based on date of hire; 10 annual paid U.S. observed holidays; 401k with a best-in-class company match; deferred compensation for eligible roles; fitness reimbursement or on-site fitness facilities; eligibility for tuition reimbursement; and many more. Mastercard benefits for interns generally include: 56 hours of Paid Sick and Safe Time; jury duty leave; and on-site fitness facilities in some locations. THIS POSTING RELECTS ONE OR MORE CURRENT VACANCIES ON OUR TEAM, AND MASTERCARD INTENDS TO FILL THIS POSITION BY 12/08/2026. Pay Ranges O'Fallon, Missouri: $115,000 - $184,000 USD

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 Software Engineer II – Notification Manager Overview The Notification Manager team is responsible for Mastercard's enterprise notification platform within the Decision Management Program (DMP). The platform processes high-volume transaction events and delivers customer-facing notifications through email, SMS, and API channels. Engineers on the team build and maintain distributed, event-driven services that support critical fraud, security, and customer engagement products. As a Software Engineer II, you will contribute to the design, development, testing, deployment, and support of backend services that power Notification Manager. You will work closely with Product, TPMs, Architects, QA, and partner engineering teams to deliver scalable, resilient, and secure solutions while continuing to grow your technical expertise. What You'll Do Software Development •Design, develop, test, and maintain Java/Spring Boot microservices. •Implement enhancements, new features, and defect fixes across Notification Manager services. •Participate in technical design discussions and translate requirements into working software. •Write clean, maintainable, and secure code following Mastercard engineering standards. •Develop and maintain automated unit, integration, and API tests. Platform Modernization •Contribute to modern event-driven architectures utilizing Kafka messaging and distributed processing patterns. •Support ongoing platform modernization initiatives, including service decomposition, resiliency improvements, performance optimization, and cloud-native deployment practices. •Help reduce technical debt and improve operational efficiency across the platform. Reliability & Operational Excellence •Participate in production support, incident response, and root cause analysis. •Monitor system health using observability tools and metrics. •Troubleshoot application, infrastructure, and data-related issues. •Support release activities and production readiness efforts. Collaboration •Work closely with engineers, QA, PMTs, TPMs, and partner teams to deliver roadmap commitments. •Participate in Agile ceremonies, elaboration sessions, estimation, and backlog refinement. •Contribute to technical documentation and knowledge sharing. •Assist and mentor junior engineers where appropriate. Required Qualifications •Bachelor's degree in Computer Science, Engineering, or equivalent experience. •2–5 years of software development experience. •Experience developing applications using Java and Spring Boot. •Understanding of REST APIs and microservice architectures. •Familiarity with messaging or event-driven systems. •Experience with source control, code reviews, and CI/CD practices. •Working knowledge of SQL and relational databases. •Strong troubleshooting and problem-solving skills. •Ability to work independently on assigned deliverables while collaborating effectively within a team. Preferred Qualifications •Experience with event-driven architectures (Kafka, MQ, or similar). •Experience with cloud platforms, PCF/Tanzu, Kubernetes, or containerized workloads. •Knowledge of distributed systems concepts including resiliency, fault tolerance, and scalability. •Experience with observability tools such as Splunk, Dynatrace, Grafana, or Prometheus. •Familiarity with CI/CD pipelines and automated testing frameworks. •Exposure to PCI, security, or regulatory requirements. •Experience working in high-volume transaction processing systems. Success Measures (First 12 Months) A successful Software Engineer II on the Notification Manager team will: •Independently deliver stories and enhancements from design through production deployment. •Contribute meaningful improvements to platform reliability, performance, or maintainability. •Demonstrate ownership of one or more Notification Manager services or technical domains. •Participate effectively in production support and incident investigations. •Build strong partnerships with Product, TPM, QA, and peer engineering teams. •Continuously improve technical knowledge and contribute to team engineering practices. Technical Environment •Java (JDK 17) •Spring Boot •Kafka Messaging •REST APIs •Oracle / SQL •GitHub / Bitbucket •CI/CD Pipelines •Splunk & Dynatrace •PCF / Tanzu •Distributed Event-Driven Architecture Ideal Candidate Profile You're someone who enjoys backend engineering, solving complex problems, and learning how large-scale distributed systems operate. You are curious, collaborative, and proactive, taking ownership of your work while constantly looking for ways to improve the platform, the codebase, and the team's engineering practices. Mastercard is a merit-based, inclusive, equal opportunity employer that considers applicants without regard to gender, gender identity, sexual orientation, race, ethnicity, disabled or veteran status, or any other characteristic protected by law. We hire the most qualified candidate for the role. In the US or Canada, if you require accommodations or assistance to complete the online application process or during the recruitment process, please contact reasonable_accommodation@mastercard.com and identify the type of accommodation or assistance you are requesting. Do not include any medical or health information in this email. The Reasonable Accommodations team will respond to your email promptly. 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. In line with Mastercard’s total compensation philosophy and assuming that the job will be performed in the US, the successful candidate will be offered a competitive base salary and may be eligible for an annual bonus or commissions depending on the role. The base salary offered may vary depending on multiple factors, including but not limited to location, job-related knowledge, skills, and experience. Mastercard benefits for full time (and certain part time) employees generally include: insurance (including medical, prescription drug, dental, vision, disability, life insurance); flexible spending account and health savings account; paid leaves (including 16 weeks of new parent leave and up to 20 days of bereavement leave); 80 hours of Paid Sick and Safe Time, 25 days of vacation time and 5 personal days, pro-rated based on date of hire; 10 annual paid U.S. observed holidays; 401k with a best-in-class company match; deferred compensation for eligible roles; fitness reimbursement or on-site fitness facilities; eligibility for tuition reimbursement; and many more. Mastercard benefits for interns generally include: 56 hours of Paid Sick and Safe Time; jury duty leave; and on-site fitness facilities in some locations. THIS POSTING RELECTS ONE OR MORE CURRENT VACANCIES ON OUR TEAM, AND MASTERCARD INTENDS TO FILL THIS POSITION BY 12/22/2026. Pay Ranges O'Fallon, Missouri: $92,000 - $147,000 USD

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 Full Stack Software Engineer Overview The Enterprise Data Catalog team builds solutions that help employees discover, understand, and use data across Mastercard. The team partners with Product, Data Science, Data Governance, and Engineering teams to improve data discovery, metadata management, and platform integration capabilities. We are seeking a Senior Full Stack Software Engineer with strong React, Angular, and Java development expertise to help build and enhance the applications that power these capabilities. This role combines application development, system integration, technical design, and collaboration across multiple teams to deliver scalable, secure, and maintainable solutions. As a Senior Full Stack Software Engineer, you will: -Design, build, and enhance enterprise applications using React, Angular, and Java. -Translate business requirements into effective technical solutions. -Contribute to technical planning, estimation, software design, architecture, testing, and delivery. -Create RESTful APIs and integrations that connect data catalog tools with -enterprise platforms and data sources. -Build capabilities that support metadata discovery, data profiling, business glossaries, search, enrichment, and bulk data uploads. -Develop services that retrieve, transform, store, and transfer data between systems. -Partner with Product Managers, Data Scientists, Data Governance professionals, and engineers to deliver roadmap priorities. -Evaluate development approaches and recommend engineering best practices. -Advance CI/CD pipelines, deployment automation, stability testing, and performance monitoring. -Implement unit, functional, and integration testing to support reliable software delivery. -Apply secure coding practices throughout the software development lifecycle. -Conduct code reviews and provide technical guidance to other engineers. -Improve application performance, scalability, reliability, observability, and supportability. -Diagnose complex application, integration, and production issues and implement lasting solutions. -Contribute to the continued improvement of team services, development standards, and DevOps practices. All About You -5+ years of software engineering experience building and supporting enterprise applications. -Strong React, Angular, and Java development expertise. -Proven success delivering scalable, multi-tier applications. -REST API design, integration, and Swagger/OpenAPI documentation. -Technical design experience within distributed systems and microservices environments. -Strong foundation in data structures, algorithms, and software engineering principles. -Experience integrating applications across databases, platforms, and data sources. -Familiarity with Oracle, PostgreSQL, SQL Server, MySQL, MongoDB, Hadoop/HDFS, or Amazon S3. -CI/CD, Jenkins, and modern DevOps practices. -Unit, functional, and integration testing methodologies. -Secure coding practices and application security fundamentals. -Code review, performance optimization, and production support experience. -Skilled at troubleshooting complex technical issues and identifying root causes. -Ability to mentor engineers and influence engineering best practices. -Adaptability to evolving technologies, priorities, and business needs. -Familiarity with data catalogs, metadata management, or data governance platforms is preferred. Mastercard is a merit-based, inclusive, equal opportunity employer that considers applicants without regard to gender, gender identity, sexual orientation, race, ethnicity, disabled or veteran status, or any other characteristic protected by law. We hire the most qualified candidate for the role. In the US or Canada, if you require accommodations or assistance to complete the online application process or during the recruitment process, please contact reasonable_accommodation@mastercard.com and identify the type of accommodation or assistance you are requesting. Do not include any medical or health information in this email. The Reasonable Accommodations team will respond to your email promptly. 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. In line with Mastercard’s total compensation philosophy and assuming that the job will be performed in the US, the successful candidate will be offered a competitive base salary and may be eligible for an annual bonus or commissions depending on the role. The base salary offered may vary depending on multiple factors, including but not limited to location, job-related knowledge, skills, and experience. Mastercard benefits for full time (and certain part time) employees generally include: insurance (including medical, prescription drug, dental, vision, disability, life insurance); flexible spending account and health savings account; paid leaves (including 16 weeks of new parent leave and up to 20 days of bereavement leave); 80 hours of Paid Sick and Safe Time, 25 days of vacation time and 5 personal days, pro-rated based on date of hire; 10 annual paid U.S. observed holidays; 401k with a best-in-class company match; deferred compensation for eligible roles; fitness reimbursement or on-site fitness facilities; eligibility for tuition reimbursement; and many more. Mastercard benefits for interns generally include: 56 hours of Paid Sick and Safe Time; jury duty leave; and on-site fitness facilities in some locations. THIS POSTING RELECTS ONE OR MORE CURRENT VACANCIES ON OUR TEAM, AND MASTERCARD INTENDS TO FILL THIS POSITION BY 12/01/2026. Pay Ranges O'Fallon, Missouri: $115,000 - $184,000 USD

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 work to connect and power an inclusive, digital economy that benefits everyone, everywhere, by making transactions safe, simple, smart, and accessible. Using secure data and networks, partnerships, and passion, our innovations and solutions help individuals, financial institutions, governments, and businesses realize their greatest potential. Our decency quotient, or DQ, drives our culture and everything we do inside and outside of our company. We cultivate a culture of inclusion for all employees that respect their individual strengths, views, and experiences. We believe that our differences enable us to be a better team – one that makes better decisions, drives innovation, and delivers better business results About the Role This is an exciting opportunity for you to join Mastercard and contribute to improving the response time for new applications that support the Authorization payment network. The performance engineering team partners with development teams to improve scalability and reliability. The focus will be to build automation, develop performance solutions, and investigate bottlenecks in applications to maximize performance in production. We are looking for an experienced engineer that is passionate about performance with a constant focus on improving system quality. Role • Design, configure, and execute performance tests and drive resolution of failures • Create performance measurements such as requests per second, P95 and P99 response latency, query performance, concurrency, and system utilization • Dig into Java code, databases, middleware, and vendor software to identify performance bottlenecks and resolve them • Improve the performance environment with your own code, automation, and external tools • Apply technical ability to coach and develop junior engineers • Deliver department and external presentations sharing results with stakeholders All About You • Strong software engineering experience writing applications using Java Spring Boot framework • Strong experience debugging performance issues with APM tools (i.e. Dynatrace, Splunk, Jprofiler, and JMH) • Strong experience optimizing DB queries in PostgreSQL and Oracle • Experience with Payments industry preferred (i.e. ISO 8583 messaging, 4-party model, and payment applications) • Systematic problem-solving approach, coupled with strong communication skills and a sense of ownership and drive • Time/project management, workload prioritization, knowledge sharing and a passion to learn/take on challenges is a must • Self-motivated demonstrating strong organizational and listening skills; and very detail oriented with the ability to carry out assigned tasks with minimal supervision • Strong verbal and written communications skills • Appetite for change and pushing the boundaries of what can be done with automation. Be curious about new technology, infrastructure, and practices to scale our architecture and prepare for future growth • Willingness and ability to learn and take on challenging opportunities and to work as a member of matrix based diverse and geographically distributed project team Mastercard is a merit-based, inclusive, equal opportunity employer that considers applicants without regard to gender, gender identity, sexual orientation, race, ethnicity, disabled or veteran status, or any other characteristic protected by law. We hire the most qualified candidate for the role. In the US or Canada, if you require accommodations or assistance to complete the online application process or during the recruitment process, please contact reasonable_accommodation@mastercard.com and identify the type of accommodation or assistance you are requesting. Do not include any medical or health information in this email. The Reasonable Accommodations team will respond to your email promptly. 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. In line with Mastercard’s total compensation philosophy and assuming that the job will be performed in the US, the successful candidate will be offered a competitive base salary and may be eligible for an annual bonus or commissions depending on the role. The base salary offered may vary depending on multiple factors, including but not limited to location, job-related knowledge, skills, and experience. Mastercard benefits for full time (and certain part time) employees generally include: insurance (including medical, prescription drug, dental, vision, disability, life insurance); flexible spending account and health savings account; paid leaves (including 16 weeks of new parent leave and up to 20 days of bereavement leave); 80 hours of Paid Sick and Safe Time, 25 days of vacation time and 5 personal days, pro-rated based on date of hire; 10 annual paid U.S. observed holidays; 401k with a best-in-class company match; deferred compensation for eligible roles; fitness reimbursement or on-site fitness facilities; eligibility for tuition reimbursement; and many more. Mastercard benefits for interns generally include: 56 hours of Paid Sick and Safe Time; jury duty leave; and on-site fitness facilities in some locations. THIS POSTING RELECTS ONE OR MORE CURRENT VACANCIES ON OUR TEAM, AND MASTERCARD INTENDS TO FILL THIS POSITION BY 06/25/2026. Pay Ranges O'Fallon, Missouri: $115,000 - $184,000 USD

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 Who is Mastercard? We work to connect and power an inclusive, digital economy that benefits everyone, everywhere, by making transactions safe, simple, smart, and accessible. Using secure data and networks, partnerships, and passion, our innovations and solutions help individuals, financial institutions, governments, and businesses realize their greatest potential. Our decency quotient, or DQ, drives our culture and everything we do inside and outside of our company. We cultivate a culture of inclusion for all employees that respect their individual strengths, views, and experiences. We believe that our differences enable us to be a better team – one that makes better decisions, drives innovation, and delivers better business results. About the Role This is an exciting opportunity for you to join Mastercard’s Transaction Switching program and improve authorization response time. Authorization sends billions of transactions among the integrated issuers, acquirers, and service providers worldwide. This position is on the performance engineering team in O’Fallon, Missouri and will partner with the development teams to performance test and tune each release. We are looking for software engineers that are passionate about creating high quality software while keeping performance top of mind. • Do you have a passion for solving complex technical challenges? • Do you love learning new technologies and apply it to your team? • Have you developed software before – preferably in C/C++? • Have you spent time in Linux environments? • Have you created scripts to automate manual tasks (i.e. shell script, TCL, Perl, Python)? • Do you understand throughput, latency, memory and CPU utilization? • Do you have experience and prefer working in an Agile environment? Role • Work closely with feature teams to identify risks and anticipate problems to ensure that each release does not negatively impact performance • Dig into the code to determine performance bottlenecks and make the improvement • Design, configure, automate, and execute performance tests • Improve the performance environment with your own code, automation, and onboarding of external tools (i.e. Dynatrace and Splunk) • Work collaboratively and effectively in a fast-paced environment All About You • Proven experience developing backend applications in a Linux environment with C and/or C++ programming language(s) • Deep knowledge and experience of computer architecture with throughput, latency, memory and CPU utilization for performance engineering to test, debug and troubleshoot performance issues. • Clear experience with automation to create scripts for manual tasks (I.e., shell scripting, TCL, Perl, Python) #AI3 Mastercard is a merit-based, inclusive, equal opportunity employer that considers applicants without regard to gender, gender identity, sexual orientation, race, ethnicity, disabled or veteran status, or any other characteristic protected by law. We hire the most qualified candidate for the role. In the US or Canada, if you require accommodations or assistance to complete the online application process or during the recruitment process, please contact reasonable_accommodation@mastercard.com and identify the type of accommodation or assistance you are requesting. Do not include any medical or health information in this email. The Reasonable Accommodations team will respond to your email promptly. 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. In line with Mastercard’s total compensation philosophy and assuming that the job will be performed in the US, the successful candidate will be offered a competitive base salary and may be eligible for an annual bonus or commissions depending on the role. The base salary offered may vary depending on multiple factors, including but not limited to location, job-related knowledge, skills, and experience. Mastercard benefits for full time (and certain part time) employees generally include: insurance (including medical, prescription drug, dental, vision, disability, life insurance); flexible spending account and health savings account; paid leaves (including 16 weeks of new parent leave and up to 20 days of bereavement leave); 80 hours of Paid Sick and Safe Time, 25 days of vacation time and 5 personal days, pro-rated based on date of hire; 10 annual paid U.S. observed holidays; 401k with a best-in-class company match; deferred compensation for eligible roles; fitness reimbursement or on-site fitness facilities; eligibility for tuition reimbursement; and many more. Mastercard benefits for interns generally include: 56 hours of Paid Sick and Safe Time; jury duty leave; and on-site fitness facilities in some locations. THIS POSTING RELECTS ONE OR MORE CURRENT VACANCIES ON OUR TEAM, AND MASTERCARD INTENDS TO FILL THIS POSITION BY 07/13/2026. Pay Ranges O'Fallon, Missouri: $115,000 - $184,000 USD