Motion Design System — David Montealegre

Context

For years, Mercado Libre — one of Latin America's largest technology ecosystems — had not focused on building motion experiences internally. A small number of motion designers handled custom animation requests on demand, while most experiences relied on basic standards such as screen transitions and the easing and duration values embedded in components like bottom sheets and snackbars.

I joined the project as an interaction analyst. My objective was to research the concepts, criteria, and practices that could become the foundation of a future system. I contributed for nine months before handing the work over to Mercado Libre's first dedicated motion design team, providing the initial groundwork for what later became its motion design system.

Initial problems

Only a few components had standardized animation behavior—for example, all bottom sheets used the same easing and duration.
The system did not define when motion should be used according to the experience objective; each team relied on individual judgment.
Teams had no shared methodology for delivering projects that required custom motion.
Motion designers were scarce—initially about one for every 80 designers—which created a bottleneck.
Motion designers were focused on delivery, leaving little capacity to define and build the system itself.

In short, the internal problem was a lack of clarity, consistency, and collective criteria for using motion.

Roadmap

The initial stage followed four steps distributed across three analysts, two UX designers, and one motion designer who joined during phase two.

1. Research and analysis

2. Foundation definition

3. Documentation

4. Subsystem expansion

Where did we focus first?

How do others approach it? We studied systems including Material Design, Human Interface Guidelines, Carbon, Spectrum, and Fluent.
What already existed internally? We reviewed custom animations at Mercado Libre to understand their process, tools, and most persistent execution and handoff frictions.
What should we define? We looked for references that could help us establish a repeatable process for creating a motion design system.

What did I contribute?

I defined the process used to create the roadmap, drawing from Val Head's Designing Interface Animation. The book gave us a practical route for taking the first steps toward a motion design system.
I researched leading motion design systems—including Material Design, Human Interface Guidelines, Adobe Spectrum, and Carbon—then aligned their commonalities and differences to define both an MVP and a more ambitious future state.
I investigated how UX and motion designers at Mercado Libre had created custom animations: the tools they used, their execution and handoff processes, and the frictions they encountered when aligning with development.
I created and developed Motion Level: a shared standard for deciding what type of animation to create based on the UX objective, flow frequency, and the user's journey.

Final result

After contributing to the project for nine months, I handed the research, framework, and documentation over to Mercado Libre's dedicated motion design team. The work continued evolving after my involvement and became part of the motion foundations currently used across the organization.

My contribution was not the final system itself, but the early research and shared decision-making framework that helped the team move from isolated animation practices toward a more consistent approach to motion.