EP
Senior Frontend Engineer

Esteban
Palacio

I build design systems and the interfaces that sit on top of them. Eight years of it — most recently leading component and token work on the Abyss Design System at United Health Group.

Based in
Toronto, ON
Core stack
React · TypeScript · GraphQL
Currently
Publicis Sapient, since 2022
Open to senior roles
United Health Group
21
shared components engineered for the Abyss V2 design system
Vulcan Materials
40+
cross-stack order bugs found and fixed
Mayo Clinic
100+
patients served by the recovery-tracking app
Le Wagon
60+
students taught across four cohorts
Experience
Publicis Sapient
Senior Full-Stack Engineer
Toronto · Apr 2022 — now
United Health Group — Abyss Design System
2023 — 2026
  • Led component API and token architecture on a micro-frontend platform, engineering 21 shared components and owning versioned releases with a 12-person cross-functional team.
  • Resolved 80+ WCAG issues to reach 93% compliance; lifted Lighthouse performance 56 → 85 and best practices 54 → 78.
  • Built Abyss Playground, a custom internal environment for live component experimentation, adopted by roughly 40% of teams, and introduced Figma Tokens for white-label theming.
  • Co-designed the team's coding standards, PR conventions and review process.
Vulcan Materials — KiboCommerce storefront admin
2026 — now
  • Built a five-step QuickOrder wizard in React and Zustand for ~80 sales reps, including an anonymous-cart path for orders placed before a customer is linked.
  • Diagnosed 40+ cross-stack bugs across the React frontend and GraphQL BFF — duplicate pay-by-link charges, timezone and service-charge errors — closing 50+ tickets and reconciling $10,000+ in erroneous charges.
  • Implemented SAML single sign-on with an OIDC fallback, and restored BFF branch coverage above 80%.
Mayo Clinic & Genoa Clinic
2022 — 2023
  • Modernised the Mayo Clinic portal: user flows, Redux state management and SSR/CSR tradeoffs, as part of a 20-person team.
  • Shipped a React Native recovery-tracking app used by 100+ patients, built under strict privacy and data-localization constraints.
  • Built survey flows, card interfaces, routing architecture and Chart.js dashboards for Genoa Clinic.
Le Wagon Canada
Frontend Instructor
Montreal · 2021 — 2022
Led frontend instruction for four full-time cohorts — 60+ students — from HTML and CSS fundamentals through TypeScript and modern UI implementation, and coached project weeks to shipped interfaces.
Marketing Automation Canada
Frontend Developer
Toronto · 2021
Shipped 30+ responsive landing pages and email campaigns across six client accounts, with Marketo and HubSpot tracking for campaign measurement.
Independent
Freelance Full-Stack Developer
Toronto · 2018 — 2021
Sole developer on four client engagements across Canada and Colombia — requirements, design, frontend and Rails backend, deployment and support.
Skills
Frontend
TypeScriptReactNext.jsReact NativeMicro-frontendsReduxZustandTailwindMUIshadcn/ui
Design systems
Token architectureComponent API designFigma TokensVersioned releasesAccessibility (WCAG)
Full-stack & APIs
GraphQLBackend-for-FrontendRESTRuby on RailsSAML / OIDCKiboCommerce
Testing & delivery
JestPlaywrightGitHub ActionsJenkinsAWS LambdaChart.js
AI-assisted
ClaudeGitHub CopilotGeminiInternal review bots
Projects

A keyboard-first Japanese kana practice app: adaptive review, a 208-entry kana curriculum, and a fully offline-installable PWA with a custom service worker for atomic build updates.

Next.jsTypeScriptSupabasePlaywrightVitestPWA
About

I came to engineering sideways. Before this I spent four years in finance in Sydney — a broker and lending manager running a A$100M loan book, building cashflow models, explaining structures to people making the largest decision of their lives. That job taught me more about interface design than any course did: if someone can't understand the number in front of them, nothing else you built matters.

Now I do the same thing in code. Most of my work lives one layer below the product — shared components, tokens, accessibility, the CI that catches things before a human has to. It's quiet work, and I like that other teams move faster because of it.

I taught for a year at Le Wagon. Outside work: four languages spoken, three more in progress, and a long-running habit of over-reading the changelog.

Education
Master of Applied Finance (Banking)
Master of Commerce (E-Commerce)
University of Wollongong
Also
BA Finance & International Affairs, Universidad Externado
Diploma, Finance & Mortgage Broking Management, AAMC Training Group
Le Wagon Tokyo, full-stack
Languages
English, Spanish — native
French — conversational
Italian, Mandarin, Japanese — learning

Let's talk.

Open to senior frontend roles at product companies. I read everything, and I reply.

Toronto, ON647-807-7673
© 2026 Esteban Palacio