Senior Software Engineer

The Trade Desk is a global technology company and the world’s leading independent platform for digital advertising, with nearly 4,000 employees across more than 30 offices. Our technology helps advertisers reach the right audiences across the open internet — from streaming TV and podcasts to mobile apps, news, and more. Advertising powers the content people love. By making it more transparent, effective, and responsible, we help support trusted journalism, quality entertainment, and creators worldwide. The world’s brands and agencies rely on us to reach their customers and grow their businesses responsibly. The scale of our platform brings unique technical challenges — from processing massive datasets in real time to building systems that operate reliably on a global scale. When you work here, your impact is worldwide. We welcome diverse perspectives, encourage curiosity, and build teams that learn from one another. If you’re driven to solve meaningful challenges, we’d love to meet you. The Team: Marketplace Quality Engineering

Every second, our bidder evaluates millions of ad opportunities across thousands of publishers and supply paths. Not all of that supply is created equal — some of it is duplicated, some is structurally inaccessible, and some degrades advertiser outcomes. The Marketplace Quality Engineering team exists to make sure our platform is buying the right impressions, not just more impressions. We own the systems that assess, measure, and optimize supply quality across the programmatic ecosystem. Our work spans deduplication, supply path analysis, quality modeling, and the tooling that turns those signals into decisions at bid time. The problems are technically deep — think identity resolution across fragmented supply chains, statistical modeling to separate signal from noise, and real-time decisioning at platform scale — and they have direct, measurable impact on both advertiser outcomes and platform economics. This is not theoretical work. When we ship a model update, spend distribution across the platform shifts. Our engineering decisions translate directly into tens of millions of dollars of measurable business impact. If you want to build systems where what you ship visibly matters, this is the team. You will work with C# / .NET as a core strength, alongside Python and SQL where data and automation need it, and partner closely with product, data, and platform teams across time zones.