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Agent guide: [/agents.md](https://www.wearedevelopers.com/agents.md). --- # Senior Integration Engineer - **Company:** Mastercard - **Location:** O'Fallon, MO, United States - **Experience:** Expert - **Salary:** $96,000.0 - $163,000.0 - **Contract:** Permanent contract - **Skills:** Java (Programming Language), Abstraction Layers, Application Programming Interfaces (APIs), JIRA, Automation of Tests, Cyber Security, Continuous Integration, Extract Transform Load (ETL), Software Debugging, Distributed Systems, Apache JMeter, Microsoft UI Automation, Object-Oriented Software Development, Systems Development Life Cycle, Selenium, Software Testing Automation Framework, Test Case, Strategies of Testing, Performance Testing, Modern Ui, Postman, Spring-boot, Cypress (Programming Language), Blazemeter, Low Latency, Restful APIs, Cucumber (Software), Data Pipelines, Api Management, SDET, Microservices - **Published:** October 2, 2026 - **Apply:** https://www.techcareers.com/job.asp?id=3414911946&tx=JT989TYI&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 * 6+ years of experience in automation-focused QA / SDET roles * Strong hands-on expertise in Java-based automation frameworks * Deep experience with: o Selenium (UI automation) o REST Assured (API testing) o Cucumber (BDD frameworks) o Cypress (modern UI automation) * Strong understanding of Spring / Spring Boot microservices architectures * Experience testing RESTful APIs in distributed systems environments * Hands-on experience with performance testing tools (JMeter, BlazeMeter) * Solid understanding of CI/CD pipelines and automated test execution * Strong analytical, debugging, and problem-solving skills Preferred Qualifications * Experience designing or evolving automation frameworks (beyond test case development) * Familiarity with test design patterns (Page Object Model, abstraction layers, BDD best practices) * Experience supporting high-scale, mission-critical systems with strict SLAs * Experience in Agile/Scrum delivery models * Exposure to containerized or cloud-based testing environments * Familiarity with test management tools (e.g., Jira, ALM) * Domain experience in billing, financial systems, payments, or card services * Experience testing data pipelines, ETL processes, or streaming systems ## Description This role is an automation-first Senior SDET position, responsible for designing, building, and maintaining robust automated test frameworks across API, UI, and performance layers. You will work closely with engineering teams to embed quality throughout the SDLC, ensuring speed, stability, and confidence in every release., 1. Automation Ownership (API & UI) 2. Design and maintain scalable, maintainable test automation frameworks using: o Java + Selenium (UI automation) o REST Assured (API automation) o Cucumber (BDD) for executable specifications o Cypress for modern UI testing where applicable * Ensure automation suites are reliable, efficient, and aligned with engineering standards * API Quality Engineering * Validate REST APIs built on Spring / Spring Boot for: o Functional correctness o Contract/schema adherence o Error handling and edge cases * Utilize Postman and Insomnia for exploratory testing and debugging, converting findings into automated coverage * Performance & Non-Functional Testing * Design and execute performance, load, and stress tests using tools such as JMeter and BlazeMeter * Define and track performance baselines across: o Throughput o Latency o Resource utilization * Partner with engineering teams to diagnose bottlenecks and optimize performance * CI/CD Integration * Integrate automation suites into CI/CD pipelines to provide rapid feedback and enforce quality gates * Enable parallel execution and efficient test runs across shared environments * Test Strategy & Quality Leadership * Contribute to test strategy, coverage planning, and risk assessment * Create high-quality defect reports with clear diagnostics and reproducibility * Lead improvements in test frameworks, processes, and engineering standards * Provide technical leadership and mentorship across QA and delivery teams, 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 - [SMART Test Automation - the experience of legacy transformation](https://www.wearedevelopers.com/videos/100215-smart-test-automation-the-experience-of-legacy-transformation) - [No more Node: Build APIs with Flask and test it with Postman](https://www.wearedevelopers.com/videos/563-no-more-node-build-apis-with-flask-and-test-it-with-postman) - [GitOps for the people](https://www.wearedevelopers.com/videos/461-gitops-for-the-people) - [Migrating half a million users to a new payment service provider](https://www.wearedevelopers.com/videos/730-migrating-half-a-million-users-to-a-new-payment-service-provider) - [Are Your APIs Ready for AI Agents](https://www.wearedevelopers.com/videos/2004-are-your-apis-ready-for-ai-agents) - [Improving quality with Agentic AI with Rovo Dev and Xray](https://www.wearedevelopers.com/videos/2005-improving-quality-with-agentic-ai-with-rovo-dev-and-xray) ## Related Articles - [How We Built a Worry-Free System That Runs for 10+ Years – And What We’d Do Again](https://www.wearedevelopers.com/magazine/751-how-we-built-a-worry-free-system-that-runs-for-10-years-and-what-we-d-do-again) - [The 8 Best Code Testing Tools](https://www.wearedevelopers.com/magazine/402-the-8-best-code-testing-tools) - [Why Upskilling And Reskilling is Important For Developers](https://www.wearedevelopers.com/magazine/428-why-upskilling-and-reskilling-is-important-for-developers) - [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’s the Difference between a Junior, Mid, and Senior Developer?](https://www.wearedevelopers.com/magazine/238-what-s-the-difference-between-a-junior-mid-and-senior-developer)