Full Stack QA Engineer
Japanese fintech company operating the PayPay mobile payments service.
Maintainer signals as of 9/2/2026
About PayPay Corporation
PayPay Corporation develops and provides electronic payment services, including the PayPay mobile payment platform. It was founded on June 15, 2018, is headquartered in Tokyo, Japan, and currently operates an active financial-services platform integrating payments with card, banking, securities, and insurance offerings.
Skills
About the Role
You will develop test scenarios and detailed test cases for functional and non-functional requirements across mobile, web, and API products. You will prepare test data, tools, and environments; execute automated and manual tests; document results; manage defects; and maintain test documentation. You will improve quality through automation, analyze and report QA outcomes, contribute to knowledge sharing, support junior QA engineers, and serve as a subject-matter expert for assigned modules. You will use AI tools and OpenAI APIs to accelerate testing, validate LLM-driven applications using prompt engineering and RAG techniques, automate API interactions, secure AI workflows, and monitor AI and ML systems for bias, drift, hallucinations, and performance deviations.
Requirements
- 3+ years of experience developing, executing, and maintaining automated test cases for mobile applications, web applications, and/or APIs
- Professional experience with Appium, Playwright, Selenium, or Rest-Assured
- Experience using Cucumber to define and execute test cases
- Knowledge of CI/CD tools such as GitHub Actions or Bitrise
- Basic understanding of microservices architecture and testing challenges
- Ability to analyze technical requirements, design test strategies, and create detailed test cases
- Experience with AI productivity tools including NotebookLM, Gemini, Cursor AI, and GitHub Copilot
- Knowledge of OpenAI API usage, key management, embeddings, and LLM integration workflows
- Familiarity with MCP server concepts and test automation pipeline integration
- Understanding of AI validation for bias, hallucinations, drift, and robustness
- Business-level English
Responsibilities
- Analyze testing requirements and develop comprehensive test scenarios
- Design detailed test cases for functional and non-functional requirements
- Prepare and manage test data, tools, and environments
- Execute test cases and scripts and document results
- Drive quality improvement through test automation and manual validation
- Log, track, and verify defects
- Collect, analyze, and report test results and QA activities
- Recommend solutions for identified issues
- Maintain test documentation for new features and regression testing
- Contribute to testing discussions, knowledge management, and continuous improvement
- Serve as a subject-matter expert for designated modules
- Guide and support junior QA engineers through onboarding and training
- Use AI tools to accelerate test design, automation, and exploratory testing
- Apply prompt engineering and RAG techniques to validate LLM-driven applications
- Automate API interactions and secure AI workflows using OpenAI keys, LLM models, and MCP server integrations
- Test and monitor AI and ML systems for bias, drift, hallucinations, and performance deviations
Benefits
- Super flex time with no core hours
- Annual leave of up to 14 days in the first year
- Personal leave
- Social insurance
- 401K
- Translation and interpretation support
- Visa sponsorship
- Relocation support
