Senior UI-UX Designer

Senior UI Designer

The Sr. UI Designer will be the design-focused voice at the intersection of design and implementation, co-owning the visual fidelity, interaction quality, and long-term evolution of Epsilon's CORE UI design system. Based in Chicago, this role partners across Product Design and Engineering to push the boundaries of what's possible in enterprise SaaS: from building future-facing prototypes that signal where the product is heading, to shipping production-ready components that improve for every team.

You bring deep fluency in design systems, a refined eye for motion and micro-interactions, and a willingness to use AI tools to move faster without sacrificing quality. This is a rare opportunity to define what delightful, modern SaaS looks like from the inside out, at a company where design has a seat at the table.

Responsibilities

• Own the ongoing evolution of Epsilon's CORE UI design system, contributing to its token architecture, component quality, and interaction standards across both Figma and production code.
• Build future-facing prototypes that explore emerging interaction patterns, next-generation UI concepts, and new product directions, communicating vision and intent before a line of production code is written.
• Rapidly iterate on existing components by applying AI-assisted workflows. Use tools like Cursor, Copilot, v0, and generative invention to shorten build-to-code cycles without losing quality or consistency.
• Define and champion a motion language for the product: easing curves, transition choreography, loading states, and micro-interactions that make complex enterprise software feel alive, responsive, and intuitive.
• Partner closely with front-end engineers to close the gap between design intent and production reality, reviewing implementations, writing production-quality CSS and component code when the moment calls for it, and setting a high bar for what 'done' looks like.
• Contribute to the design system's documentation, usage guidance, and adoption, making it easier for every product team to build with consistency and confidence.
• Stay at the forefront of AI-native design practices: identifying where AI tools can accelerate exploration, reduce repetitive work, and enable higher-quality outcomes at scale.
• Collaborate with Product Designers on complex interaction flows, ensuring that every edge case, empty state, and loading moment is thoughtfully designed and accounted for.
• Mentor and set a high standard within the design org, leading by example in design critiques, system reviews, and cross-functional handoffs, and raising the quality bar for the team around you.
• Apply WCAG accessibility standards throughout component and interaction design, advocating for inclusive experiences at the system level.

Qualifications

What you'll bring with you:

• Six or more years of experience in UI development, engineering, creative engineering, or a related hybrid field. A portfolio must show shipped SaaS or digital product work.
• Deep, hands-on experience contributing to and evolving a design system across both Figma (component libraries, design tokens, documentation) and code (React components, Storybook, token pipelines).
• A strong and opinionated motion sensibility: experience designing and implementing micro-interactions, transitions, and animation systems that feel purposeful, polished, and on-brand, not decorative afterthoughts.
• Demonstrated proficiency using AI tools, such as Cursor, Git Hub Copilot, v0, Framer AI, or similar to accelerate design-to-code workflows, rapid prototyping, and component iteration.
• Fluency in high-fidelity interactive prototyping, capable of producing experiences that convincingly simulate a final product to validate ideas before full build.
• Working knowledge of HTML, CSS (including animations, transitions, and custom properties), and JavaScript/Type Script sufficient to implement and critically review production UI.
• Excellent visual design judgment: typography, spacing, color, density, and layout decisions that hold up at both the component and product-surface level.
• An accessible online portfolio featuring live, interactive work and demonstrated motion and interaction work, not only static screens.

Why you might stand out from other talent:

• You've built or significantly contributed to a design system that scaled across multiple product teams and you have strong, battle-tested opinions on what makes a system actually get adopted, not just built.
• Your portfolio includes motion and interaction work: easing references, transition demos, or prototypes where the 'how it moves' was as deliberate and considered as 'what it looks like.'
• You've used AI tools not just to write code faster, but to fundamentally change how you explore, prototype, and validate design directions, treating AI as a creative partner, not a shortcut.
• You are equally comfortable opening a Figma file to iterate on a component's states as you are opening a code editor to implement that same component in code.
• You believe enterprise…