Principal Software Engineer, Yahoo Mail

Yahoo Mail is the ultimate consumer inbox with hundreds of millions of users. It’s the best way to access your email and stay organized from a computer, phone or tablet. With its beautiful design and lightning fast speed, Yahoo Mail makes reading, organizing, and sending emails easier than ever.

A Little About Us

Yahoo makes the world's daily habits inspiring and entertaining. By creating highly personalized experiences for our users, we keep people connected to what matters most to them, across devices and around the world. Yahoo Mail Backend Team develops and maintains high-performing systems that provide API (Web Services, IMAP, & POP), Metadata, and Elastic Storage for electronic mail and its auxiliary functions. Handling billions of requests a day for approximately 300 million active monthly users across mobile, desktop, and web clients, the team works on complex challenges spanning from high-throughput web services down to operating system and networking layers.

Yahoo Mail teams in three words: Your personal database. We are looking for an advanced technical leader who views AI as an essential accelerator to scale their personal and team impact, and who thrives in an evolving, AI-augmented development environment.

Responsibilities

• Architect, design, and guide the development of high-performing, scalable, and highly available backend systems for Yahoo Mail using Java and C++ on Unix/Linux platforms.

• Drive technical strategy and establish unified architectural standards across multiple engineering squads for mail APIs, low-latency metadata systems, and elastic storage solutions.

• Identify and implement AI-driven efficiencies in backend engineering, leveraging approved AI-assisted tools (e.g., CodeWhisperer Professional / Amazon Q Developer) to replace manual, repetitive coding and unit testing tasks with optimized workflows.

• Act as a technical validator, establishing the standards for reviewing, refining, and testing AI-generated architectural proposals and code outputs to ensure strict security, performance, and style compliance.

• Mentor senior engineering staff, conducting rigorous design and system reviews while fostering a culture of continuous learning, technical curiosity, and experimentation.

• Collaborate actively with cross-functional stakeholders—including Product Management, Design, Security, and Cloud Infrastructure teams—to translate product visions into scalable technical architectures.

• Diagnose and resolve complex, multifaceted system anomalies, establishing automated logging, telemetry, and debugging workflows to ensure world-class platform reliability.

Minimum Qualifications

• BS in Computer Science (or equivalent practical experience) with a minimum of 8 years of professional software engineering experience.

• Specialized expertise in high-concurrency backend development using Java, C++, and Unix/Linux systems.

• Deep conceptual and practical understanding of computer science fundamentals (data structures, multi-threading, memory management, and advanced algorithms).

• Solid experience with search algorithms, as well as the design and query optimization of both Relational and NoSQL database architectures.

• Demonstrated experience utilizing developer-facing AI productivity tools (such as CodeWhisperer or Copilot) to accelerate code output, optimize design patterns, and streamline testing.

• Strong understanding of HTTP and TCP/IP protocols, with experience troubleshooting network-level performance and latency constraints.

• Proven track record of technically leading complex engineering initiatives with minimal guidance and guiding teams through ambiguous technical challenges.

• Strong written and verbal communication skills, with an ability to articulate complex technical ideas to both technical and non-technical stakeholders.

Preferred Qualifications

• Experience designing, deploying, and operating highly distributed, large-scale mail applications and standard communication protocols.

• Familiarity with leveraging secure LLM endpoints and frameworks (e.g., AWS Bedrock / SageMaker) for metadata tagging, intelligent search, or backend telemetry analysis.

• Comprehensive experience with continuous integration and continuous deployment (CI/CD) pipelines, containerization (Docker, Kubernetes), and modern test automation frameworks.

• Deep practical experience with GCP or AWS cloud architectures, particularly in managing hybrid cloud migration