QA Engineer

Company DescriptionCredlock powers micro-credit through device collateralized lending. Our platform features a custom-built device risk management system, providing loan decision-making and funding for merchant-initiated transactions from financial partners, as well as loan lifecycle management for the merchants on our platform. Our mission is to foster a competitive marketplace of lenders and ultimately reduce the cost of borrowing for customers across Africa.About the RoleWe are hiring a QA Engineer with strong backend testing experience. You will focus on ensuring the quality, stability, and performance of our server-side systems. Our stack includes Node.js, NestJS, and microservice-style APIs, with supporting interfaces built in React.js, Next.js, and React Native.Key ResponsibilitiesDesign and execute test plans specifically for backend services and APIs.Develop automated tests for Node.js and NestJS endpoints.Validate data processing, business logic, authentication flows, and error handling.Perform load, stress, and performance testing on backend services.Work closely with backend engineers to debug issues and improve system reliability.Ensure consistent behavior across integrations with frontend and mobile clients.Maintain clear documentation for test cases, automation scripts, and QA workflows.RequirementsProven experience as a QA Engineer focused on backend or API testing.Strong understanding of backend architecture, REST APIs, and microservice patterns.Hands-on experience with API testing tools (Postman, Insomnia, Newman, etc.).Experience with automated testing frameworks (Jest, Supertest, Cypress API mode, Playwright API mode).Ability to test asynchronous flows, queues, jobs, and background processes.Good grasp of MongoDB or SQL database behaviors in testing environments.Solid debugging, documentation, and communication skills.Nice to HaveExperience with CI/CD pipelines and automated QA in deployment workflows.Exposure to containerized environments (Docker).Experience testing distributed systems or asynchronous workers.Security testing knowledge (auth, rate limits, input validation).