Fabricio Pirini

Senior Frontend Engineer building fintech products for web and mobile.

React, React Native, Expo, and Next.js. Brazil (UTC−3), working with US teams.

Building something in fintech? I'm happy to chat.

Now · Building a pre-launch US consumer fintech's Expo and React Native app for iOS, Android, and web, plus its Next.js admin, from the first commit.

Selected work

Pre-launch US consumer fintech 2026–now

One codebase for iOS, Android, and web, from the first commit

What I did
Set up the TypeScript monorepo with one Expo and React Native app for iOS, Android, and web, plus a Next.js admin. Built the theme tokens, with a CI check that fails when the design spec drifts from the theme.
Result
Every pull request is gated on lint, type checks, unit tests, and Playwright end-to-end runs at desktop and mobile viewports.
  • Expo
  • React Native
  • Next.js
  • Playwright

Kraken 2024–2026

In-app support portal across three React Native apps

What I did
Built it from scratch with tier-aware contact options, VIP escalation, and live queue visibility. Owned it end to end: frontend, backend integration, and rollout.
Result
Shipped in Kraken, Kraken Pro, and Krak.
  • React Native
  • TypeScript

Kraken 2024–2026

Financial data tables, visual regression tests, and accessibility fixes

What I did
Built 15+ financial data tables and the Playwright visual regression infrastructure from scratch. Fixed 25+ accessibility issues: keyboard navigation, focus management, and ARIA attributes.
Result
Visual tests dropped from 12 minutes to under a minute, and coverage tripled across the component library.
  • Financial tables
  • Playwright
  • Accessibility

Experience Building since 2017

  1. 2026–nowPre-launch US consumer fintechExpo, React Native, and Next.js from the first commit.
  2. 2024–2026KrakenOwned the design system and shipped to 4 platforms.
  3. 2022–2024Norsk GjenvinningTech lead for 5 engineers. Built 5 Next.js storefronts and led WCAG 2.0 AA compliance across 70+ European companies.
  4. 2020–2022OdaBuilt the A/B experimentation program from scratch and ran 2 to 4 experiments a month.
  5. 2018–2020SportradarRebuilt the crawler platform as 5 microservices, cutting runtime by 120x and resource usage by 10x.
  6. 2017–2018Samsung R&D CenterIntern. Built a WCAG 2.0 AA web accessibility portal.

About

I moved to Norway straight after graduating for my first full-time engineering job, stayed six years, and now work from Brazil.