Staff Software Engineer, Demand Bidder, Ad Serving Platform

About the Team

Roku's Ad Serving Team builds and operates the real-time advertising platform that powers all of Roku’s ad monetization across video, display, and native ad formats. Within Ad Serving, the Demand Bidder team owns the high throughput and low latency systems responsible for serving relevant ads for tens of thousands of campaigns through targeting, scoring, bidding, auctions, measurement and more. Every millisecond and every decision carries direct, measurable revenue impact, and the team operates with high engineering rigor.

About the Role

We're hiring a Senior Software Engineer (Staff scope) to help scale and evolve this platform. Demand Bidder is a large, high-throughput system driving our next phase of growth. As we onboard a rapid wave of new businesses, we are actively scaling and advancing our architecture — including a state-of-the-art pacing engine, scoring/ML engine, and modularizing designed for agentic development.

What You'll Be Doing

• Design, build, and operate core components of a large-scale, real-time distributed decisioning system with strict latency requirements.
• Take end-to-end ownership of specific subsystems: architecture, implementation, testing, deployment, on-call, and long-term evolution.
• Build a working mental model of a highly distributed, complex production system, and make high-leverage contributions.
• Identify opportunities to continuously evolve the system and tooling.
• Partner with engineers and applied scientists working at the intersection of distributed systems and statistical/ML-driven decision-making.
• Diagnose and resolve subtle, often timing- or statistics-related issues in a highly concurrent, multi-region distributed system.
• Mentor other engineers and raise the bar on engineering rigor, testing discipline, and operational excellence across the team.
• Communicate clearly with both technical and non-technical stakeholders, and drive alignment across engineering, product, and business partners.

Qualifications

• 10+ years of experience designing, building, and operating large-scale, low-latency distributed systems — ideally including at least one system built substantially from the ground up.
• Demonstrated track record of owning complex systems end-to-end: design, build, operate, on-call, and iterate based on production feedback.
• Proven ability to ramp quickly on unfamiliar, complex, large codebases and become productive fast.
• Experience evolving and refactoring live, business-critical systems without compromising uptime or correctness.
• Strong command of Java, with a solid foundation in algorithms, data structures, concurrency/multi-threading, and performance optimization.
• Practical experience with distributed caching, high-throughput messaging/streaming systems, and SQL/NoSQL datastores.
• Comfort operating in cloud infrastructure (GCP or AWS) at scale.
• Exposure to applying statistical, control-theory, or ML-driven techniques within production decision-making systems is a strong plus.
• Real-time bidding / ad-tech domain experience or deep experience in adjacent high-stakes, low-latency domains (trading systems, large-scale ranking/recommendation, matchmaking, risk/fraud systems) is valued.
• Experience using AI coding assistants (e.g., Claude Code, Cursor, or similar) to accelerate design, implementation, debugging, and code understanding is welcomed.
• B.S. or M.S. in Computer Science, Engineering, or equivalent practical experience.