Principal Frontend Web Engineer, Yahoo Mail

Principal Software Web Engineer

We are seeking a Principal Software Web Engineer who will lead the next generation of communication products on the web and set the technical direction for how our team builds in an AI‑First world. As a Principal, you will operate as both an architect and a validator of high‑quality code, orchestrating AI‑assisted workflows to accelerate delivery while maintaining architectural judgment, security posture, and user experience that millions of users rely on.

You will mentor engineers, explore new technology, and turn rough ideas into elegant, production‑grade products.

• Feature Leadership & Delivery:
  Define, design, develop, and ship major new features in current and future web products, owning them end‑to‑end from requirements through production monitoring.
• AI‑First Workflow Orchestration:
  Leverage approved AI‑assisted tools such as Cursor and Claude Code to accelerate implementation while maintaining architectural integrity, code quality, and security.
• Lifecycle Optimization:
  Identify and implement AI‑driven efficiencies across the development lifecycle, replacing manual boilerplate and repetitive refactors with automated, AI‑validated workflows.
• Technical Judgment & Oversight:
  Balance AI‑generated outputs with manual oversight, reviewing generated code for architectural correctness, performance, and adherence to strict accessibility and security standards.
• High‑Scale Impact:
  Take ownership of web application areas impacting millions, tackling hard engineering and UX problems with elegant, seamless solutions.
• Quality &
  
  Collaboration:
  
  Perform thorough code reviews and collaborate with UX designers and product managers to deliver platform improvements and critical bug fixes.
• Operational Excellence:
  Write testable, reliable code and deploy, monitor, and operate large‑scale production web systems distributed across the globe.
• Mentorship & Innovation:
  Mentor engineers across the squad and adjacent teams to scale AI‑first best practices, establish guardrails for AI‑augmented coding, and evaluate emerging tooling to keep Yahoo at the leading edge.

• BS in Computer Science (or equivalent) with 8+ years of professional software engineering experience.
• Strong understanding of data structures, algorithms, and software design fundamentals.
• Deep technical knowledge of responsive design and modern JavaScript frameworks such as React and Angular, and Node.js.
• Expertise in web application development with a strong command of browser‑side technologies including HTML5, CSS3, Type Script, and OOP JavaScript.
• Proven expertise in software development principles, design patterns, CI/CD, and deployment architecture.
• Experience with modern web technologies like Webpack, Redux Toolkit, Atomic CSS, Storybook, and REST APIs.
• Expertise in test‑driven development and frameworks such as Jest, Selenium, Playwright, and React Testing Library.
• Expert knowledge of web application performance, stability, and debugging.
• Hands‑on experience with approved AI code‑assist tools such as Cursor and Claude Code integrated into daily development workflows.
• Proficient in writing clear prompts, engineering context‑rich system prompts, and iterating on AI suggestions to achieve robust implementation results.
• Commitment to evaluating and validating AI‑generated outputs to detect logical errors, security vulnerabilities, and code regressions.

• Experience developing Mail or Calendar applications.
• Experience with ML and GenAI, including building user‑facing features powered by LLMs.
• Experience working in Unix/Linux environments.
• Experience with mobile web development.
• Experience with Scrum, Squad, or similar agile development methodologies.
• Exposure to accessibility (a11y) or internationalization (i18n) for large‑scale systems.

Compensation for this position ranges from $ to $ per year and may include incentive compensation opportunities such as discretionary annual bonuses or commissions. Our comprehensive benefits package includes healthcare, a 401(k) plan, backup childcare, education stipends, and additional perks.

Yahoo is a proud equal‑opportunity workplace. All qualified applicants…