Senior Backend Engineer, Yahoo Mail – Contacts Platform

Yahoo Mail Contacts Platform Engineer

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.

The preferred job location for this role is Bangalore, Karnataka.

About Yahoo Mail's Contacts Platform

Contacts Platform is Yahoo Mail's contacts aggregation, relationship, and recommendation platform. It is a large-scale distributed system that enhances users' address books based on their communication history, powers contacts search and compose auto-suggest, and underpins contact-based experiences across Yahoo Mail.

The platform serves hundreds of millions of users and handles billions of requests every day with low latency and high reliability. The platform demands extreme reliability, resilience, and performance, and it tackles some of the toughest challenges in distributed systems, architecture design, algorithms, and data engineering.

Come join an amazing team of engineers, product managers, and designers building next-generation contact and relationship experiences that transform how users connect with each other every day on Yahoo Mail.

Responsibilities

• Architectural Leadership & Implementation: Architect and implement innovative features and high-performance REST web services. Drive technical decisions and provide leadership on high-impact projects, ensuring elegant architecture and thoughtful design.
• Mission-Critical Service Development: Develop and enhance core, mission-critical services, including those utilizing protocols like CalDAV, caching mechanisms, and large-scale data processing, handling hundreds of billions of transactions daily.
• Product Delivery & Code Quality: Lead the design, implementation, testing, and debugging of features. Ensure the delivery of high-quality, reliable, and testable code through continuous deployment and rigorous code reviews for peers.
• Team & Technical Influence: Lead, influence, and coach a distributed team of engineers, fostering a culture of continuous learning. Share knowledge and mentor team members, and recommend alternative technical approaches to complex problems, leveraging new technology to achieve ambitious goals.
• Complex Problem Solving: Take ownership of significant application features, tackling hard engineering and user experience problems to deliver elegant and seamless solutions that directly impact millions of users.
• Cross-Functional Collaboration: Collaborate effectively with product managers and other engineers to define requirements, explore solutions, and deliver new features, enhancements, platform improvements, and bug fixes. Understand and balance tradeoffs across product, user experience, security, privacy, legal/compliance, and operations to arrive at pragmatic solutions.
• Where applicable, leverage AI/ML techniques (including GenAI) to improve contact quality, deduplication, ranking, and recommendations.

Qualifications

• 8+ years of hands-on software development experience, including 2+ years as a lead engineer driving complex projects end-to-end and building scalable high-performing distributed systems.
• B.S. or M.S. in Computer Science or a related field, or equivalent practical experience.
• Strong experience with cloud-native application development on AWS, GCP or Azure. Experience with GCP is a strong plus, especially with services such as GKE, Dataflow/Apache Beam, Pub/Sub, and Spanner (or similar technologies on other clouds).
• Deep expertise in distributed systems: highly scalable, low-latency serving systems; stream and batch data processing; event-driven architectures.
• Proven track record of building and operating highly scalable, performant, and reliable backend systems in production.
• Demonstrated ability to lead team initiatives, influence technical direction, and collaborate effectively with Production Engineering/DevOps, Frontend, Product, and UX.
• Solid programming skills in one or more modern languages (e.g., Java, Scala, Go, or similar), with strong fundamentals in data structures, algorithms, and concurrency.
• Experience in API development, SQL and NoSQL databases and distributed caches.
• Experience using AI/ML and GenAI development tools (e.g., Cursor, Claude Code, GitHub Copilot) for building and operating production systems is a strong plus, as our team heavily uses AI-assisted development on a daily basis.
• Demonstrated ability to use modern AI coding assistants (e.g., GitHub Copilot, Cursor, Claude) to accelerate development tasks such as code generation, refactoring, debugging, and documentation.
• Stay current with evolving AI-assisted development tools and practices; Contribute to improving team-wide workflows involving AI-assisted engineering.
• Help define best practices for AI-assisted development.