Senior QA Engineer

About us:
Working at Tech Holding isn't just a job, it's an opportunity to be a part of something bigger. We are a full-service consulting firm that was founded on the premise of delivering predictable outcomes and high-quality solutions to our clients.  Our founders and team members have industry experience and have held senior positions in a wide variety of companies – from emerging startups to large Fortune 50 firms – and we have taken our combined experiences and developed a unique approach that is supported by the principles of deep expertise, integrity, transparency, and dependability.
About the Role
We are looking for a Senior QA Engineer (SDET) to support a critical automation projects. This role will focus on API testing, automation, and end-to-end quality assurance across the transaction lifecycle.
Key Responsibilities
API Testing
Perform API testing for integrations using tools like Postman / REST clients.
Test routing logic.
Test Automation & Quality Engineering
Extend and maintain automated test suites workflows and APIs.
Build API automation frameworks (using JavaScript, Java, or Python).
Integrate automated tests into CI/CD pipelines for continuous validation.
Functional & Edge Case Validation
Test success, failure, and edge-case scenarios (timeouts, retries, duplicate transactions).
Validate idempotency and error handling mechanisms.
Perform exploratory and manual testing for complex workflows.
Data Validation & Reconciliation
Validate transaction data across APIs and databases.
Write and execute SQL queries for backend validation.
Performance & Reliability Testing
Conduct basic load and performance testing for payment APIs.
Validate system behaviour  under high transaction volume.
Monitor and report latency, failure rates, and retries.
Production Rollout & Monitoring
Support production deployment validation and pilot rollout.
Monitor transaction success rates and error logs post-release.
Collaborate on issue triaging and quick resolution.
Requirements
5+ years of QA experience with strong focus on API and backend testing.
Hands-on experience with API testing tools (Postman, REST Assured, etc.).
Good to have experience with Playwright
Experience in test automation using JavaScript, Java, or Python.
Experience with SQL and database validation.
Knowledge of CI/CD pipelines and automation integration.
Understanding of HTTP protocols, REST APIs, and JSON.
Familiarity with error handling, retries, and distributed system behaviors.
Strong analytical, debugging, and problem-solving skills.
Good to Have
Experience with performance testing tools (JMeter, k6, etc.).
Exposure to Agile/Scrum methodologies.
Tech Holding is proud to be an Equal Opportunity Employer and is committed to fostering a diverse and inclusive workplace. We welcome applicants from all backgrounds and experiences, and we consider qualified applicants without regard to race, color, religion, gender, sexual orientation, gender identity, national origin, disability, veteran status, or any other legally protected characteristic. If you require accommodation in the application process, please contact our HR