Senior Software Engineer

Location: O'Fallon, Missouri

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

Who is Mastercard?

Mastercard is a global technology company in the payments industry. Our mission is 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. With connections across more than 210 countries and territories, we are building a sustainable world that unlocks priceless possibilities for all.

Overview

We are seeking an experienced Senior Software Engineer with strong expertise in Golang, cloud-native application development, and AWS-based solutions to support Mastercard's Cloud Connect initiatives. The role will focus on building secure, scalable connectivity platforms that enable customers to connect to Mastercard services from public cloud environments and private networks through modern cloud-native architectures.

Role

• Design, develop, and maintain secure, scalable, and resilient cloud-native applications and services using Golang and AWS technologies to support Mastercard's Cloud Connect initiatives.
• Collaborate cross-functionally with product, architecture, engineering, and operations teams to design scalable solutions, systems, APIs, and databases that meet functional and non-functional requirements.
• Contribute to software architecture, technical design reviews, and architectural decision-making, ensuring solutions are maintainable, performant, secure, and aligned with enterprise standards.
• Design and optimize data structures, algorithms, and processing patterns to support high-volume distributed systems and efficient resource utilization.
• Participate in the complete software development lifecycle, including requirements analysis, design, development, testing, deployment, monitoring, and ongoing support.
• Design, develop, and maintain automated unit, functional, and integration tests while promoting test-driven development practices.
• Conduct code reviews and provide technical mentorship to engineering team members, promoting coding standards, software quality, maintainability, and engineering best practices.
• Apply secure coding principles throughout the software development lifecycle, proactively identifying and remediating vulnerabilities through code reviews, security testing, and adherence to Mastercard security standards.
• Contribute to operational excellence by implementing observability, monitoring, logging, alerting, and reliability best practices for cloud-native services.
• Perform root cause analysis, troubleshoot complex production issues, and lead performance tuning efforts to improve system reliability, scalability, and efficiency.
• Work with business partners and stakeholders to understand business needs and translate requirements into technical solutions.

All About You

• Bachelor's degree in Computer Science, Management Information Systems, Engineering, or related field.
• 7+ years of software engineering experience designing, developing, and supporting enterprise applications.
• 2+ years of hands-on experience developing applications using Go (Golang).
• Experience designing, deploying, and operating cloud-native solutions on AWS.
• Strong understanding of AWS networking services including VPC, Transit Gateway, PrivateLink, Route 53, Network Load Balancers, and Direct Connect.
• Experience building and operating containerized applications using Kubernetes, Amazon EKS, Docker, and related cloud-native technologies.
• Strong understanding of distributed systems concepts, scalability patterns, performance optimization, and efficient data structure design.
• Experience conducting code reviews and promoting engineering best practices, software quality, and secure coding standards.
• Knowledge of secure software development practices including authentication, authorization, encryption, secrets management, vulnerability remediation, and application security testing.
• Experience implementing and maintaining automated testing frameworks, including unit, functional, and integration testing.
• Experience with Test-Driven Development (TDD) methodologies.
• Experience with protocol buffers and gRPC.
• Experience with Python 3.8 or higher is preferred.
• Strong understanding of CI/CD pipelines and modern DevOps practices using Git, Jenkins, Artifactory, Docker Registry, and related technologies.
• Experience building and supporting applications on Linux platforms.
• Experience implementing observability and operational readiness practices including logging, monitoring, alerting, and incident response.
• Agile software delivery experience in a globally distributed engineering environment

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 [email protected] 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

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 01/12/2027. If the fill date has passed, Mastercard intends to fill this position as soon as possible.

Pay Ranges

O'Fallon, Missouri: $115,000 - $184,000 USD