Fullstack Software Dev Engineer II

About the role

We are looking for a Full Stack Software Dev Engineer II to join our Identity organization. You will work across the stack to build secure, scalable, and user-friendly authentication and account management experiences that serve hundreds of millions of users globally. In this role, you will work independently with minimal guidance, owning critical features and acting as a technical resource for your peers.

Responsibilities

• Design, build, and operate secure, scalable full-stack identity systems using ReactJS, TypeScript, Java, and Node.js.
• Own complex features and standalone project phases end-to-end, from gathering requirements and systems design to implementation, testing, and production.
• Led an AI-first development workflow within the squad, writing precise markdown specifications to drive AI-assisted code generation (Cursor, Claude Code), and taking responsibility for the rigorous validation, testing, and safety of all generated assets.
• Identify system bottlenecks, enhance platform reliability, and debug complex production issues in our high-traffic distributed identity systems.
• Proactively research and implement AI-driven efficiencies in your daily coding workflows, replacing repetitive manual tasks with structured automation, custom templates, and AI-assisted testing.
• Act as a technical resource for the team by sharing successful prompt engineering patterns, context modeling strategies, and workflow optimizations that level up the overall engineering velocity of the squad.
• Collaborate cross-functionally with Product Managers, UX Designers, Security Engineers, and other Yahoo product squads to coordinate technical integrations.

Qualifications

• Bachelor’s degree in Computer Science, a related technical field, or equivalent practical experience.
• 4–6 years of professional full-stack software engineering experience.
• Strong hands-on engineering experience using Java for robust backend services.
• Experience building responsive, high-performance web applications using React.js, Node.js, JavaScript/TypeScript, and modern frameworks such as Next.js.
• Strong core engineering fundamentals in distributed system design, API development, databases, and web security.
• Demonstrated experience integrating AI-assisted developer tools (e.g., Cursor, Claude Code, GitHub Copilot) into day-to-day software development workflows to build and refactor production-grade systems.
• Practical understanding of prompt engineering, model limitations, and structured context assembly to generate robust code outputs.
• Proven capability to evaluate, audit, and debug AI-generated outputs, ensuring alignment with Yahoo’s high standards for code quality, security protocols, and performance.
• Experience with testing frameworks, CI/CD pipelines, and writing production-ready, highly maintainable tests.