Senior Principal Software Engineer, Ads Quality

Snap Inc is a technology company. We believe the camera presents the greatest opportunity to improve the way people live and communicate. Snap contributes to human progress by empowering people to express themselves, live in the moment, learn about the world, and have fun together. The Company operates Snapchat , a visual messaging app that enhances your relationships with friends, family, and the world, and Specs Inc. , a wholly-owned subsidiary dedicated to making computing more human, in addition to Bitmoji , Saturn, and other digital services. Snap Engineering teams build fun and technically sophisticated products that reach hundreds of millions of Snapchatters around the world, every day. We’re deeply committed to the well-being of everyone in our global community, which is why our values are at the root of everything we do. We move fast, with precision, and always execute with privacy at the forefront. We’re looking for a Senior Principal Software Engineer to lead the technical direction of Ads Quality within Snap’s Ads Platform team, with a focus on Ads Marketplace. Our marketplace connects advertiser demand with opportunities across Snapchat, deciding how budgets are spent, which ads are shown, and when and where they appear. As a senior individual contributor, you will shape the multi-year strategy and architecture for bidding, pacing, auctions, inventory and traffic optimization, and ad reranking. You will work across engineering, product, data science, and ML teams to improve advertiser performance and grow sustainable revenue while delivering a relevant, engaging experience for Snapchatters. What you’ll do: Set the multi-year technical strategy and architecture for Ads Marketplace, connecting investments across bidding, pacing, auctions, inventory, traffic optimization, and ad reranking. Design and scale bidding, budget allocation, and pacing algorithms that help advertisers achieve their goals with efficient spend and predictable delivery under changing marketplace conditions. Advance auction mechanisms, pricing, and allocation algorithms to improve advertiser value and marketplace efficiency, accounting for interactions with ranking, bidding, and pacing. Lead inventory and traffic optimization across Snapchat surfaces, improving ad load, placement, and demand allocation while balancing monetization with long-term user engagement. Develop ad reranking and slate optimization approaches that account for relevance, diversity, repetition, and the surrounding user experience, in partnership with Ads Ranking and consumer product teams. Establish objectives, evaluation methods, and experimentation standards that measure incremental marketplace impact, account for feedback loops and interference, and protect advertiser and user outcomes. Lead complex initiatives across teams, resolve architectural trade-offs and dependencies, and stay hands-on through prototyping, critical implementation, and production problem solving. Raise the engineering bar for reliability, latency, scalability, and cost efficiency; mentor senior engineers and technical leaders, and build shared technical foundations that enable teams to deliver independently. Knowledge, Skills & Abilities: Deep expertise in one or more areas of ads marketplace optimization, with the ability to reason about interactions across bidding, pacing, auctions, ranking, and user experience. Strong foundations in algorithms, optimization, statistics, and distributed systems, with the judgment to choose practical approaches for real-time production environments. Excellent programming and software design skills, including debugging, performance analysis, testing, and operating highly available systems at scale. Ability to turn ambiguous business and technical problems into a coherent strategy, measurable objectives, and an executable roadmap across multiple teams. Strong technical judgment in balancing advertiser outcomes, revenue, user engagement, system complexity, and operational risk. Ability to influence across organizational boundaries, communicate complex trade-offs clearly, and develop senior engineers and technical leaders. Minimum Qualifications: Bachelor’s degree in a technical field such as computer science, mathematics, or statistics, or equivalent practical experience. 10+ years of post-Bachelor’s software development experience; or a Master’s degree in a technical field and 10+ years of post-graduate software development experience; or a PhD in a related technical field and 7+ years of post-graduate software development experience. 3+ years of experience providing technical leadership or serving as a domain expert for a technical organization. Experience setting technical direction and leading complex engineering initiatives across multiple teams, from architecture through production delivery and measurable impact. Experience architecting, building, and operating large-scale distributed systems. Preferred Qualifications: Proven track record of delivering significant improvements in advertiser performance, marketplace efficiency, or revenue through ads bidding, pacing, auction, or inventory optimization. Experience applying machine learning, constrained optimization, control theory, or online learning to budget allocation and real-time marketplace decisions. Experience with auction theory, mechanism design, pricing, or market dynamics in production advertising systems. Experience with ad reranking, slate optimization, ad load, placement, or frequency optimization that balances monetization with user engagement and long-term value. Experience designing marketplace experiments and causal evaluation methods that account for interference, feedback loops, delayed outcomes, and ecosystem effects. "Default Together" Policy at Snap: At Snap Inc. we believe that being together in person helps us build our culture faster, reinforce our values, and serve our community, customers and partners better through dynamic collaboration. To reflect this, we practice a “default together” approach and expect our team members to work in an office 4+ days per week. At Snap, we believe that having a team of diverse backgrounds and voices working together will enable us to create innovative products that improve the way people live and communicate. Snap is proud to be an equal opportunity employer, and committed to providing employment opportunities regardless of race, religious creed, color, national origin, ancestry, physical disability, mental disability, medical condition, genetic information, marital status, sex, gender, gender identity, gender expression, pregnancy, childbirth and breastfeeding, age, sexual orientation, military or veteran status, or any other protected classification, in accordance with applicable federal, state, and local laws. EOE, including disability/vets. We are an Equal Opportunity Employer and will consider qualified applicants with criminal histories in a manner consistent with applicable law (by example, the requirements of the San Francisco Fair Chance Ordinance and the Los Angeles Fair Chance Initiative for Hiring, where applicable). Our Benefits : Snap Inc. is its own community, so we’ve got your back! We do our best to make sure you and your loved ones have everything you need to be happy and healthy, on your own terms. Our benefits are built around your needs and include paid parental leave, comprehensive medical coverage, emotional and mental health support programs, and compensation packages that let you share in Snap’s long-term success! Compensation In the United States, work locations are assigned a pay zone which determines the salary range for the position. The successful candidate’s starting pay will be determined based on job-related skills, experience, qualifications, work location, and market conditions. The starting pay may be negotiable within the salary range for the position. These pay zones may be modified in the future. Zone A (C