Senior Software Engineer

Senior Software Engineer | Microsoft Careers Skip to main content Microsoft Careers Careers Careers Search Search jobs Sign in Single PositionView All JobsSenior Software EngineerUnited States, Washington, Redmond +1 moreApply nowAdd to cartFind out how well you match with this jobUpload your resumeJob descriptionCompany and benefitsJob number200044427Date postedJul 17, 2026Work site4 days / week in-officeTravelLess than 25%ProfessionSoftware EngineeringDisciplineSoftware EngineeringRole typeIndividual ContributorEmployment typeFull-TimeOverviewThe Microsoft Advertising Mediation Service (MMS) is the real-time auction and mediation platform that sits at the heart of Microsoft's advertising stack. Built on Go and derived from Prebid Server, MMS processes OpenRTB traffic at global scale across multiple Azure regions, running header-bidding auctions, executing bidder filtration, applying dynamic reserve pricing, and powering experimentation across Microsoft's owned-and-operated and third-party supply (Outlook, MSN, Xandr, LinkedIn, MSAN, and more). We are looking for a Senior Software Engineer to set the technical direction for MMS as it scales to the next order of magnitude of traffic, supply types, and auction complexity. This is a deeply technical IC role: you will own architecture decisions that span the request hot path, the experimentation framework (flights/TSGs), bidder adapter ecosystem, and the Azure-native infrastructure that runs it all. You will partner closely with engineering leads, PMs, data science, and partner teams across Microsoft Advertising to shape the roadmap, raise the engineering bar, and mentor senior engineers across the org. Microsoft’s mission is to empower every person and every organization on the planet to achieve more. As employees we come together with a growth mindset, innovate to empower others, and collaborate to realize our shared goals. Each day we build on our values of respect, integrity, and accountability to create a culture of inclusion where everyone can thrive at work and beyond. Starting January 26, 2026, Microsoft AI (MAI) employees who live within a 50- mile commute of a designated Microsoft office in the U.S. or 25-mile commute of a non-U.S., country-specific location are expected to work from the office at least four days per week. This expectation is subject to local law and may vary by jurisdiction.ResponsibilitiesTechnical LeadershipOwn the long-range architecture of the MMS platform: the OpenRTB request hot path, auction engines (best-price, priority, dynamic reserve price, multi-placement), bidder adapter framework, and the experimentation/flights system.Drive cross-team technical strategy with peer principals across Microsoft Advertising — bidders, supply integrations, brand safety, identity, measurement, and billing.Set and enforce engineering standards through design reviews, code reviews, technical RFCs, and mentorship of senior and staff-level engineers.Identify and resolve systemic risks across reliability, latency, cost, and correctness before they reach production.Service & Platform DevelopmentDesign and build highly scalable Go services on the MMS platform, with strict latency and availability SLAs measured in single-digit milliseconds and five nines.Evolve the bidder adapter framework to support new supply types (display, native, video) and new integration patterns (server-side header bidding, deal-based, programmatic guaranteed).Improve the auction subsystem — pricing, filtration (L1 brand safety, IP blocks, embargoes), bidder selection, and response shaping — with measurable revenue and quality impact.Strengthen the experimentation framework (flights, traffic sub-groups) so PMs and data science can ship A/B tests safely at high cadence.Improve observability of the request path: structured Event Hub logging, sampling strategies, metrics, and tracing across...