UX Engineer, LLM Experimentation Platform

The Opportunity

Most engineering teams treat UX refinement as an afterthought squeezed between feature work. We're carving out a dedicated role for it because we believe the difference between "works" and "delightful" is what separates good products from great ones. You'll have the space to really care about craft.

We're a technical team building for technical users (ML engineers, researchers) who are drowning in complexity. Your job is to make that complexity manageable and maybe even enjoyable. We're looking for an engineer who obsesses over the details that make complex tools feel effortless. You'll work on our LLM evaluation and prompt experimentation platform, taking functional features and refining them into intuitive, polished experiences.

What You’ll Do

• Refine and iterate on UX for existing features - you won't build from scratch, but you'll make things significantly better
• Watch real users struggle in Fullstory, identify friction points, and fix them
• Prototype interaction alternatives rapidly (in Figma or code) to test different approaches
• Work closely with our Senior engineers who own feature architecture - they build the foundation, you perfect the interface
• Own the "feel" of the product: transitions, feedback, error handling, progressive disclosure
• Build reusable interaction patterns that the team can leverage
• Run lightweight usability tests to validate improvements

A typical week might include:

• Watching 10 user sessions, identifying 3 common friction points
• Prototyping 2 different flows for evaluator configuration in Figma
• Implementing the winner with smooth transitions and helpful inline guidance
• Pairing with Staff engineers to refactor a complex form into a multi-step wizard
• Running a quick usability test with 5 users on the new onboarding flow

You're a great fit if:

• You've made products noticeably better through interaction refinement (show us!)
• You're comfortable with modern frontend frameworks and animation libraries
• You've used session replay tools and incorporated user feedback into designs
• You can work in Figma to prototype before committing to code
• You think about edge cases, loading states, and empty states automatically
• You've worked on complex tools (dev tools, data tools, B2B SaaS) where UX really matters
• Bonus: You've built or contributed to design systems

What you DON'T need:

• Formal design training (though it's welcome)
• Full-stack experience (we have engineers for that)
• Experience with our specific tech stack (we care more about your UX sensibility)

The estimated annual salary for this role is between $175,000 - $200,000, plus a competitive equity package. Actual compensation is determined based on a variety of job-related factors that may include transferable work experience, skill sets, and qualifications. Total compensation also includes a comprehensive benefits package, including medical, dental, vision, a 401(k) plan, unlimited paid time off, a generous parental leave plan, and additional support for mental health and wellness.

While we are a remote-first company, we have opened offices in New York City and the San Francisco Bay Area, as an option for those in those cities who wish to work in-person. For all other employees, there is a WFH monthly stipend to pay for co-working spaces.