Software Engineer II: Scalable Java Backend & Angular UI

Mastercard; O’Fallon (MO); On-site; USD 92,000 - 147,000; Full time

Benefits offered by this job

Health insurance

401(k) match

Paid time off

Job summary

Mastercard is seeking a Software Engineer II in O’Fallon, MO to build scalable backend services with Java/Spring Boot and frontend UI with Angular and Node.js. You will work across a distributed architecture, owning end-to-end delivery from design to production support in a secure, scalable environment.

The role sits at the intersection of site reliability, platform, and release engineering, requiring collaboration with cross-functional teams to deliver production‑grade solutions and

Qualifications

• Strong hands-on experience in Java, Spring Boot, and REST APIs.
• Hands-on experience with Angular (2+) and Node.js.
• Experience building and maintaining scalable, production-grade applications.
• Strong problem-solving, troubleshooting, and debugging skills in distributed systems.
• Knowledge of secure coding principles and vulnerability prevention techniques.
• Experience performing code reviews and contributing to engineering quality standards.

Responsibilities

• Design, develop, and own Java-based backend services and REST APIs in a distributed architecture.
• Build and enhance UI applications using Angular and Node.js.
• Own end-to-end delivery including solution design, development, testing, deployment, configuration, documentation, and operational support.
• Participate in technical design sessions, architectural reviews, and solution planning for scalable, secure software solutions.
• Ensure high-quality code through peer reviews, automated testing, and adherence to standards.
• Design, develop, and maintain unit, functional, and integration tests.
• Apply secure coding standards and security best practices throughout development lifecycle.
• Drive engineering best practices including architecture, performance, resiliency, and observability.
• Analyze performance and implement optimization improvements.
• Troubleshoot production issues and perform root cause analysis.

Skills

Java

Spring Boot

REST APIs

Angular

Node.js

Distributed systems

Secure coding

CI/CD

Cloud (Kubernetes/AWS/Azure)

Code reviews

Tools

Kubernetes

AWS

Azure

CI/CD pipelines

Job description

Mastercard is seeking a Software Engineer II in O’Fallon, MO to build scalable backend services with Java/Spring Boot and frontend UI with Angular and Node.js. You will work across a distributed architecture, owning end-to-end delivery from design to production support in a secure, scalable environment.

The role sits at the intersection of site reliability, platform, and release engineering, requiring collaboration with cross-functional teams to deliver production‑grade solutions and