Principal UX Engineer, Ads

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Reddit’s Ads Design & Research team shapes the end-to-end advertising experience across advertiser tools, consumer ad experiences, measurement, and the systems that connect them.

We’re looking for a Principal UX Engineer who sees code as a product-design medium: a way to make ideas tangible, connect prototypes to real systems and data, and help teams move from exploration to engineering-ready product direction faster.

This is a strategic, hands-on role at the intersection of design and engineering. You’ll work across Reddit Ads to shape product direction, build production-adjacent prototypes and tools, and help establish UX Engineering as a capability for the Ads Design team.

You’ll partner closely with Design, Research, Product, Engineering, and Data Science while staying deeply involved in the craft.

What You’ll Do

• Define and lead the UX Engineering strategy across multiple areas of Reddit Ads.
• Build high-quality functional prototypes, workflow tools, agents, and PR-ready product experiences that help teams explore ideas, test assumptions, and move faster from design intent to engineering review.
• Partner with senior cross-functional leaders to shape product direction and bring clarity to complex, ambiguous opportunities.
• Create reusable tools, systems, components, and workflows that make it easier to move from design and research into production.
• Raise the bar for interaction quality, accessibility, performance, and technical craft across the Ads experience.
• Build AI-native workflows, skills, agents, and tools that improve how Ads Design explores, prototypes, collaborates, and ships.
• Mentor other practitioners and help grow UX Engineering as a capabili