> Markdown version of [/jobs/ext/3266751-software-engineer-i](https://www.wearedevelopers.com/jobs/ext/3266751-software-engineer-i). Every page supports `.md` or `Accept: text/markdown`. Links point to the HTML versions so they work for humans too. Agent guide: [/agents.md](https://www.wearedevelopers.com/agents.md).

---

# Software Engineer I

- **Company:** Mastercard
- **Location:** O'Fallon, MO, United States
- **Experience:** Starter
- **Salary:** $72,000.0 - $115,000.0
- **Contract:** Permanent contract
- **Skills:** Java (Programming Language), Artificial Intelligence, Application Performance Management, Automation of Tests, Unit Testing, Software Quality, Cyber Security, Continuous Integration, Data Structures, Java Platform Enterprise Edition (J2EE), Java Persistence API, Spring Framework, Performance Tuning, Scrum Methodology, Secure Coding, Software Engineering, Transaction Processing (Computing), Test-Driven Development (TDD), Spring-boot, Software Application Programming, Integration Tests, Apache Kafka, Restful APIs, Microservices
- **Published:** September 16, 2026
- **Apply:** https://www.techcareers.com/job.asp?id=3394178769&tx=KK6363FFJ&pt=1&aff=0B19D771-A501-4A5E-8338-2A822B784D54&utm_source=Job%20Feed&utm_medium=textkernel&utm_campaign=DE&utm_term=0B19D771-A501-4A5E-8338-2A822B784D54

## About the Role

Good understanding of Java, J2EE, Spring, Spring Boot, Kafka, RESTful Web Services, and JPA.

-Foundational understanding of software design and architecture concepts.

-Familiarity with unit, functional, and integration testing practices.

-Understanding of secure coding principles.

-Strong problem-solving and analytical skills.

-Strong understanding of data structures and their impact on application performance.

-Exposure to microservices and cloud-native application development.

-Knowledge or experience with AI-assisted applications, AI agents, or agentic workflows is a plus.

-Exposure to CI/CD practices and Test-Driven Development.

-Strong communication skills and willingness to learn from experienced engineers.

## Description

The Software Development Engineer is an early-career software engineer specializing in Java development with a focus on building microservices that support Mastercard's high-throughput, low-latency transaction processing platforms. This role provides opportunities to learn modern software engineering practices while contributing to the development, testing, deployment, and support of business-critical applications.

What You Will Do

-Develop software solutions by translating product requirements into technical implementations with guidance from senior engineers.

-Contribute to software design discussions and propose scalable, maintainable solutions.

-Write modular, readable, and performant code following engineering best practices.

-Develop and maintain unit tests and automated test coverage to validate software quality and reliability.

-Participate in functional and integration testing activities across applications and services.

-Follow secure coding standards and software engineering best practices throughout the development lifecycle.

-Participate in peer code reviews and incorporate feedback to improve code quality and maintainability.

-Assist with prototyping and proof-of-concept initiatives.

-Support cloud-ready microservices and distributed applications.

-Assist in troubleshooting and resolving software defects and production issues.

-Build applications with maintainability, reliability, and operational readiness in mind.

-Collaborate closely with cross-functional teams using Agile Scrum methodologies., 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.


## Related Videos

- [Next Level Enterprise Architecture: Modular, Flexible, Scalable, Multichannel and AI-Ready?](https://www.wearedevelopers.com/videos/1017-next-level-enterprise-architecture-modular-flexible-scalable-multichannel-and-ai-ready)
- [Rest API Antipatterns](https://www.wearedevelopers.com/videos/100208-rest-api-antipatterns)
- [How to Benchmark Your Apache Kafka](https://www.wearedevelopers.com/videos/76-how-to-benchmark-your-apache-kafka)
- [Enterprise-Cloud-Native - Fast-Paced Development & Deployment in a Highly Secure Banking Environment](https://www.wearedevelopers.com/videos/671-enterprise-cloud-native-fast-paced-development-deployment-in-a-highly-secure-banking-environment)
- [REST In Peace: Why LLMs Can't CRUD](https://www.wearedevelopers.com/videos/100272-rest-in-peace-why-llms-can-t-crud)
- [Let's Get Started With Apache Kafka® for Python Developers](https://www.wearedevelopers.com/videos/565-let-s-get-started-with-apache-kafka-for-python-developers)

## Related Articles

- [7 Important Tips That Every Software Developer Should Know](https://www.wearedevelopers.com/magazine/101-7-important-tips-that-every-software-developer-should-know)
- [Software Engineer Career: Things You Should Know](https://www.wearedevelopers.com/magazine/143-software-engineer-career-things-you-should-know)
- [Is Software Engineering Over-Saturated?](https://www.wearedevelopers.com/magazine/418-is-software-engineering-over-saturated)
- [Highest Paying Tech Companies for Developers](https://www.wearedevelopers.com/magazine/220-highest-paying-tech-companies-for-developers)
- [What is Software Engineering?](https://www.wearedevelopers.com/magazine/289-what-is-software-engineering)
- [Best Countries for Software Engineers](https://www.wearedevelopers.com/magazine/267-best-countries-for-software-engineers)