Senior UX Engineer, Prototyping Platforms

This role is completely remote-friendly. If you happen to live close to one of our physical office locations, our doors are open for you to come into the office as often as you'd like.

The Reddit Proto team plays a pivotal role in bridging the gap between ambitious product and design vision and engineering reality. As we scale, the team is responsible for moving the organization beyond one-off, disposable prototypes toward robust, reusable infrastructure. Our goal is to operationalize experimentation, empowering researchers and designers to test hypotheses with live data at the speed of thought.

As a Senior UX Engineer on the Reddit Proto Team, you will lead the evolution from one-off, disposable prototypes to a robust platform for scaled experimentation. Inspired by the concept of an “invention factory,” you will architect the modular systems that allow us to test bold ideas with internal stakeholders and external users alike. Your work will operationalize innovation, turning the Proto Team into a strategic, data-generating force that ensures our ability to explore, validate, and invent the future of Reddit scales alongside our user base.

You will take ownership of the technical strategy for design validation, influencing how Reddit measures the success of new features before they enter production. This requires a unique blend of full-stack engineering capability, systems thinking, and a deep understanding of user-centered design principles. You will inspire the team to move faster and push the quality bar of our internal tooling.

Responsibilities:

• Shape the vision: Define the technical architecture for Reddit’s prototyping ecosystem. You will lead the strategy for how we transition from static designs to interactive, data-driven experiments.
• Build the platform: Architect and maintain a robust, web-based (React, Next.js) prototyping environment. This infrastructure must be flexible enough to allow for dynamic swapping of screens and journeys for scaled A/B testing.
• Accelerate velocity: Partner closely with UXR to drastically reduce the time-to-insight for complex product questions. You will automate the “grunt work” of testing, building tools that allow us to deploy quantitative tests to hundreds of users with minimal overhead.
• Bridge the gap: Act as the translation layer between Design concepts and Production engineering. You will manage real data flows to create experiences that feel authentic, ensuring we are testing relevance rather than “happy-path” illusions.
• Tooling leadership: Identify repetitive workflows within the design organization and build internal tools or component libraries to solve them. If we are building it twice, you build the tool that automates it.
• Mentorship: Cultivate a culture of technical curiosity within the design team, establishing best practices for prototype engineering, performance, and code quality.

Required Qualifications:

• Experience: 5+ years of experience in UX Engineering, Design Technology, or Frontend Development, with a focus on building systems, platforms, or complex internal tools.
• Technical Mastery: Deep expertise in the modern web stack (React, Next.js, Node, Firebase, Cursor). You are comfortable setting up infrastructure and architecture, not just polishing UI.
• Systems Thinking: A portfolio or track record demonstrating the ability to build scalable frameworks, component libraries, or testing environments rather than just single-use websites.
• Strategic Leadership: Ability to identify “time sinks” in the design process and autonomously propose and build technical solutions to remove them.
• Bias for Action: You are a self-unblocker who thrives in ambiguity. You know when to hack for speed to prove a concept and when to engineer for stability to support a platform.
• Design Fluency: You speak the language of designers. You understand interaction design, accessibility, and the importance of fidelity in user research.
• Proven Impact: A track record of shipping internal tools or platforms that have measurably improved team efficiency or product outcomes.

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