Hello,
my name is Jules Simplicio.

I'm a design technologist at Mozilla. I co-founded Firefox's design system, Acorn, and I've led it ever since, in Figma and in code.

Firefox Nova Redesign

Nova shipped in Firefox 157 in September 2026, about seven months after engineering started landing it. The release notes call it Firefox's biggest visual refresh in years, built with our updated design system. During it, component usage nearly doubled and token coverage went from about 40% to over 60%. I reviewed the work that synced Nova's design tokens from Figma into code, and taught teams how to use our tokens and components so they could update their own features.

Firefox Settings Redesign

I led the modernization and redesign of Firefox Settings, which shipped in Firefox 152 in June 2026 with a new look, clearer groupings, and easier navigation. It's built entirely with Acorn's reusable components and patterns.

Design Tokens

I wrote and landed our first design tokens and kept growing them until they covered color, type, and our reusable patterns. Style Dictionary turns one JSON file into both Figma variables and CSS, and I started a work group so desktop and mobile stay in sync. Today about 70% of Firefox's stylesheet values use tokens, up from under 1% in 2023.

Storybook & Web Components

I went out of my way to find an engineering partner, and together we started Acorn's Storybook and web components library. I plan the roadmap, review the work, and land fixes and improvements. In 2023 we had 3 components used 10 times. Now there are 34, used over 1,000 times across Firefox.

Figma Libraries

I established Firefox's official component and style libraries in Figma and kept them in sync with what shipped in code.

Icon Package

I set up Acorn's icon package and its release process, which delivers icons to both Figma and code. It's shipped 500+ icons across 170+ releases since 2023.

Docs & Advocacy

I co-created Acorn's documentation site and have written 12 issues of our newsletter since 2021. We're a remote team, so I lead weekly coworking sessions and take turns hosting office hours. I also give talks about the system at work weeks and on company-wide calls, and for a while I ran a design systems meetup for all of Mozilla.

I designed web and mobile social media publishing features for Sprout Social.

I contributed to Sprout's design system Seeds by designing, developing, and documenting user interface components and patterns.

I also developed a Figma plugin that organized and prepared team files for design and handoff.

Seeds Design System

Breadcrumb component docs, with a live demo and code.

I designed web and mobile products for qualitative user research at dscout during a big platform-wide redesign, and worked on their first library of UI components and patterns in both design and code.

Platform Redesign

The project dashboard from dscout's redesign.

I kicked off my career with short-term jobs in web design, front-end development, and product design. At the time, I also contributed to open-source projects through the Open Source Design community.