Patrick Mullin
Design Systems Architect & UX Leader · Chicago, IL · Open to Remote
Senior UX leader and design system architect with 20+ years building and managing enterprise products at The Trade Desk and Google. Founded and architected Harbor, TTD’s first design system, and led its migration to a new visual language: every design token remapped on a two-month timeline with zero consumer-facing breaking changes. Previously built Google’s first cross-product design system, adopted by 196 teams across 24 product areas, while managing UX teams of up to 11 across the U.S., U.K., and China. Equally comfortable shaping a design system with my own hands and scaling the team that builds it.
- patmullin@gmail.com
- 773.633.5138
- patmull.in
How I Build Systems
- Adoption is the metric. I instrument systems and treat consumption data (insertions, MAU, asset views) as the roadmap. A component nobody inserts is a defect.
- Governance before components. Token architecture and contribution models first. The library is the output, not the strategy.
- I ship the front-end. Production implementations across multiple frameworks, not specs handed to engineering.
- AI belongs inside the system, not beside it. Built Harbor-governed React prototyping on Claude Code so generated work inherits the system instead of drifting from it.
Work Experience
The Trade Desk
Feb 2024 – Sep 2026 | Chicago, IL
- Principal User Experience Designer
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- Led Harbor’s migration to Zuma, the new visual language for Kokai, TTD’s flagship advertising platform, shipped August 2026 on a two-month timeline: rebuilt the color, typography, spacing, and elevation foundations and re-tokenized the system from 368 to 470 design tokens (83 rebound, 131 added, 30 retired), growing the semantic layer by roughly half. Zero consumer-facing breaking changes.
- Took 22 components and 4 foundations through design QA to a versioned engineering freeze, introducing a semver release model keyed on backwards compatibility so engineering could build against a specific design version instead of a moving target.
- Built the AI tooling behind the migration: a Figma-connected system that reads every styling parameter off a component, maps each to its design token, and generates handoff documentation complete enough that engineering migrated components with AI instead of hand-coding each update.
- Founded and architected Harbor, defining the component model, design tokens, accessibility standards, and front-end implementation that govern Kokai; 97 production components power 2.76M+ live instances across designer Figma files, with 164,725 new insertions (May 2026).
- Drove adoption across the organization: 873 registered users across 20+ countries, with roughly 92 monthly actives against a 90 MAU license.
- Built and led the team behind Harbor, up to three designers reporting to me plus four contractors across the engagement, driving its roadmap, governance, and adoption; engaged user base grew 25% year-over-year on a flat registered footprint.
- Drove procurement of Frontify as TTD’s first enterprise design system documentation platform after a competitive evaluation against Zeroheight and Bynder, supported by a comprehensive business justification.
Mar 2008 – Aug 2023 | Remote & Chicago, IL
- Sr. Staff UX Manager, Ads Design System – 2018 – 2023
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- Built Google’s first enterprise design system, adopted by 196 teams across 24 product areas, by leading the architecture, components, and front-end across 2 web frameworks and managing 7 UX Designers, 2 UX Researchers, and 9 contractors.
- Saved Google 15,000+ hours of design and engineering by delivering 60+ reusable components with full accessibility guidelines, Figma & Sketch assets, and front-end implementations.
- Launched a universal density system for Google’s desktop enterprise products, scoring 4.71/5 for usefulness and 4.92/5 for ease of use in user testing.
- Recipient of the 2020 Ads Luminary Award for establishing the vision of an enterprise design system that extends Google Material with greater cohesion and accessibility.
- Sr. Staff UX Manager, Design System Management (DSM) Tool – 2018 – 2021
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- Designed and shipped the official design system management tool for all of Google, adopted by 75 product teams in 56 countries. Recipient of the 2021 Ads Tech Impact Award.
- Defined product strategy and design direction in partnership with engineering leadership; managed 2 UX Designers and 1 UX Researcher.
- Designed core flows enabling teams to document and share their design systems as a single source of truth.
- Staff UX Designer, Publisher UX – 2014 – 2018
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- Led a cross-continental UX Design and Research team of 11 across the U.S., U.K., and China for three display ads publisher products: DoubleClick for Publishers (DFP) Sales, DFP Reservations, and DoubleClick Ad Exchange (AdX).
- Reduced implementation bugs by 20% by instituting a new UX review process that gave 30+ cross-functional partners structured visibility into in-progress work.
- Defined product roadmaps and drove alignment across engineering, product, and leadership.
- Sr. UX Designer, DoubleClick Ad Exchange – 2010 – 2014
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- Designed a new pricing and blocking control system and a unified sales tool for the DoubleClick Ad Exchange (a $2.1B/year product), delivering $500M+ ARR uplift and unlocking an additional $150M ARR.
- Led 3 UX Designers and 1 UX Researcher on the AdX team.
- UX Designer, Google Affiliate Network – 2008 – 2010
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- Designed and front-end developed the post-acquisition migration of the Performics Affiliate Network into Google Affiliate Network, applying Google’s brand and design language across the ads suite.
DoubleClick / Performics
2000 – 2008 | Chicago, IL
- Front-end Web Developer & Sr. Front-end Web Developer, Affiliate Network
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- Led design and front-end development of the Performics Affiliate Network through and after the DoubleClick acquisition, delivering hi-fidelity mockups, prototypes, and production code.
Education
Indiana University | Bloomington, IN
B.S. in Business Administration
Major: Computer Information Systems