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Fabien Rousselot

Senior Product/UX Designer

Fabien Rousselot

Senior Product/UX Designer

Auction Mobility Design System

Mobile, Web,
NOV 2021 > DEC 2022

Built the foundations of Auction Mobility’s design system to unify our product experience, reduce UI inconsistencies, and help developers ship faster.

The Challenge
When Growth Outpaced Structure

As more clients rolled in, our production pipeline simply couldn’t keep up.  Inconsistent UI, repeated manual work, mismatched components, and color systems weren’t accessible or scalable.

Years of rapid growth had created design debt, and without a shared language across teams, even simple global edits became time-consuming. Brand launches slowed down, and the product began to feel increasingly fragmented.

A Fragmented Ecosystem Slowing Everyone Down

We needed more than a facelift — we needed a future-friendly foundation. A unified, structured system that simplified collaboration, strengthened visual consistency, and made us faster across the entire delivery chain.

Our new approach had to support accessible color frameworks, reusable components, and clear documentation, all working together to deliver a cohesive experience for every auction house, on every device.

The plan

With the team, I led a full cross-platform full mapping of UI components, patterns, and variants. This became the backbone of our shared dictionary, giving designers and engineers a common language and making collaboration dramatically smoother.

  • Unified Naming & Shared Language — established consistent names for components, variants, and variables, giving designers and engineers a single, reliable vocabulary across teams and platforms.
  • Multi-Brand Architecture — restructured the system to support multiple white-label brands by separating colors into dedicated brand files, making updates cleaner, scalable, and easier to maintain.
  • Shared Atom Library — built a shared library for small, reusable components used across web, mobile, and internal tools to help reduce clutter.
  • Foundational Design Tokens — built tokens for color, spacing, and typography to support scalable theming.
  • Central Documentation — created a comprehensive, accessible source of truth so designers, engineers, and PMs could align effortlessly and adopt the system at scale.
+40%
Design to Dev Handoff

Shared language and a clean structural foundation let designers and engineers collaborate with far less friction.

-30%
Design Inconsistencies

Strengthened design foundations decreased irregularities across all products and improved overall harmony.

x3
On-boarding Capabilities

Improved rollout efficiency let sales move faster, fully assured the system could support expanding demand.

A Future-Friendly Solution

Multi-brand Architecture

I introduced a new file structure more suited to efficiently support our growing client base by separating shared foundations from brand-specific layers. This modular approach made the system easier to maintain, faster to scale, and smarter to adapt as more brands were added over time.

Flexible Color Management

From Gaps to a Cohesive System

We rebuilt our color management approach by auditing every UI element and uncovering inconsistencies and accessibility gaps. The result was a cleaner, intentional color structure that removed noise, strengthened brand identity, and kept every client theme consistent across the product.

Branding made easy

One Modular product for all

Tokens were created for all UI elements needing color changes and grouped into a single collection. This let us test palettes in real time and move fast while keeping visuals consistent globally. Since only colors changed—not the product—this system made branding much simpler and ensured each client got a look that felt uniquely theirs.

Unified Bid States

One important aspect of our products that needed some clean up were the bid states. An effort was made to simplify them make them consistent throughout the different platforms while using universal components. This helped reduced the clutter and reinforce our uniformity.

Introducing Variations

The new architecture made it possible to introduce targeted variations for key screens like auctions or lot review. These micro-customizations introduced the possibility to offer variations of our white-label product, giving each client a stronger sense of uniqueness without increasing system complexity.

Classic header style vs. full image for the lot review screen.

Minimalist approach vs. classic cards layout for the auctions screen.

Responsive Board

All designs were elaborated with the largest and smallest devices always in mind, leaving no room for surprises on web, mobile and also responsive web.

One Modular product for all

I approached my new designs with all feedback and knowledge accumulated, building a flexible new line of products, easier to implement and with a better integration of the customers’ colors.

Dedicated Tablet Design

We introduced some designs adapted to our tablet users (approx. 10%) and took advantage of the full real screen real estate, including dedicated layout work for the landscape views.

What I learned
Growing Into Systematic Thinking

This project was my real introduction to systematic design. Rebuilding our foundation forced me to think beyond screens and flows and truly understand how large products scale. I learned the technical backbone of design systems — tokens, structure, naming, accessibility, documentation — and it completely reshaped the way I design. Today, I naturally think in patterns, constraints, maintainability, and long-term impact.

A More Technical, Scalable Mindset

Working on this system sharpened my technical depth and taught me how design connects to architecture. I realized you can’t ship a major design system all at once — you have to structure it methodically, start small, and build momentum with clear milestones. That “little victories” approach now guides how I tackle any complex problem.

Advocacy and the Language of Value

Design systems don’t sell themselves. A big part of the work was advocating for it — explaining the benefits, showing the long-term value, and aligning teams who all had different priorities. I learned to speak the language of money, efficiency, and risk reduction to earn stakeholder support. System work is cultural work as much as it is design work.

Long Live the System

Above all, this project taught me that a design system is never “done.” After the advocacy and the build comes the ongoing care — monitoring how teams use it, guiding adoption, and refining it as the product evolves. Even though the rollout ended early due to the acquisition, the foundation we created proved how structure and stewardship can transform collaboration and quality.

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Fabien Rousselot

Senior UX/Product Designer

With 12+ years of experience designing user-centered digital products, I create intuitive and engaging interfaces across mobile, web, and desktop. My work spans the full design process—from research to prototyping—with a strong focus on scalable design systems that ensure consistency and efficiency.

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