Principal Software Engineer, Ads Product

Reddit is the home of conversation on the internet. Our Ads Engineering organization is responsible for the technology that fuels Reddit’s mission, connecting millions of users with brands through authentic, non-intrusive, and highly effective advertising experiences.

We are seeking a Principal Software Engineer (L7) to serve as the technical anchor for our ads product engineering efforts. Reporting directly to the Senior Director of Engineering, you will span a diverse engineering portfolio that includes Ad Formats (the consumer-facing ad experience), Ads Manager (the advertiser-facing operational tool), Ads Safety (brand suitability and verification), and Solutions Engineering (business integrations).

This is a product-oriented technical leadership role. You will not just be solving scale problems; you will be solving business problems through architecture. You will define how Reddit builds ads products for the next 3-5 years, ensuring we can iterate rapidly on new customer experiences while maintaining rigorous technical standards and a cohesive suite of offerings.

What You’ll Do

• Technical Strategy: Operate across the company, partnering with Consumer Product, Core Infrastructure, and Trust & Safety leadership to align technical roadmaps. You will identify company-level problems and drive solutions that benefit the entire engineering organization
• Cross-Domain Architecture: Architect systems that span the entire Reddit stack.
• Organizational Transformation: Identify bottlenecks in how our teams build software—whether technical (legacy debt, slow CI/CD) or organizational (siloed teams, unclear contracts)—and drive systemic changes to resolve them. You will solve hard technical and organizational problems.
• Mentorship: Serve as a beacon of engineering excellence, specifically mentoring Sr. Staff (L6) and Staff (L5) engineers. You will help them navigate career growth, technical challenges, and influence, raising the bar for the entire ~100-person organization
• Full-Stack Agnosticism: Whether your background is primarily Frontend or Backend, you will own the end-to-end technical solution. You will ensure that API designs enable performant UIs and that data models support future product flexibility.

Who You Might Be

• A Product-Centric Technologist: You care deeply about the user experience (both redditors and advertisers). You evaluate technical trade-offs based on user value and business velocity, not just pure engineering elegance.
• An Organizational Influencer: You have a proven track record of solving problems that require both code changes and people/process changes. You can influence VPs and Directors as effectively as you can code.
• Ads Domain Expert: You understand the complexities of the ad tech ecosystem—auctions, attribution, privacy (ATT/SKAdNetwork), brand safety, and campaign management.
• Force Multiplier: You have a history of m