Senior React Native Engineer

Ciaran Fontein

I build mobile apps from Figma to the App Store. 6 years shipping Guusto's iOS + Android app as its sole frontend developer.

  • 6+ years
  • sole developer
  • iOS + Android
  • 📍 Nara, Japan · Remote or Osaka
  • No visa sponsorship required
  • Available August 2026
Ciaran Fontein

About

I'm a mobile engineer. For six years I was the only frontend developer on Guusto's React Native app, which I built from scratch and shipped to both stores. My work covered the whole pipeline. I took Figma designs and turned them into TypeScript code, handled native integrations and client-side push, and did the release work that keeps an app on the stores, like cert renewals, store review rejections, and crash triage. I'm based in Japan on a spouse visa, so I don't need sponsorship. I'm a native English speaker and I'm learning Japanese. I worked fully remote for all six years, first from Canada, then Australia, then Japan, with the same Vancouver team the whole time. The time gap ran as wide as 16 hours. In practice I wrote a clear handoff note at the end of my day and read Slack at the start of it.

Featured work

Guusto app icon

Guusto · Recognition & Rewards · iOS + Android · React Native

Sole Frontend Developer, March 2020 – July 2026

I was the only frontend developer on Guusto's mobile app. I built it from scratch, shipped it to both stores, and handled every release for six years.

Guusto is an employee recognition platform. It has a 4.9 rating on G2 and Capterra, and its customers include Marriott and the Toronto Raptors. It's built for frontline workers such as nurses and drivers, who don't usually check work email. The mobile app is how those workers receive and redeem their rewards. An employee gets a gift on their phone and redeems it at a store.(App context only; web platform built by a separate team.)

What I did

  • Designed the app architecture and built it from scratch in React Native + TypeScript, working from Figma designs, and shipped it to both stores.
  • Integrated the app with Guusto's backend REST APIs.
  • Implemented the app's client-side push notification handling (receiving, displaying, and routing notifications).
  • Owned six years of continuous delivery: feature development, bug fixes, performance work, and release management for every version on both stores.
  • Shipped features across the app's life: notification center, Google Sign-In, wallet integration, activity feed with department/location filters, multi-recipient recognition, AI-assisted message suggestions, physical Mastercard/Visa card support, and the v4.13 home experience redesign (June 2026).
  • Worked directly with the web, backend, design, and product teams, from requirements through release, on a Bitbucket and Jira workflow.
  • Used Claude Code and Codex in my daily work, mostly for code review and other routine work.
  • Spent the last three months on handover as engineering moved to HQ hours: wrote the documentation, trained the incoming team, and answered their questions until my contract ended.

The closest call

A backend change broke gift sending days before Guusto's busiest week, in the middle of a code freeze. The fix was one line.

A few days before December 18, which is our busiest week of the year, we found out that users couldn't send gifts at all. If it had stayed broken, no one could have sent a gift during the highest-volume week of Guusto's year. A backend change earlier that week had broken the request format, and we were already in code freeze. QA's position was that nothing ships during a freeze. The core function of the app was down, so leaving it broken was the bigger risk. The fix turned out to be one line: the properties in the API request payload needed to be reordered. I tested it, released it, and gift sending kept working through the holidays. The director of engineering had left the decision to me, because I was the one who'd shipped every release before it.

  • 6+ years sole ownership
  • 2 platforms from one codebase
  • 4.0★ App Store
  • v4.13.0 current (June 2026)
  • releases every 4–6 months or as features complete

Screenshots

Screens from the Guusto app, which I built and shipped.

Side project · Astro · TypeScript

This website

I designed and built this site from scratch with Astro and TypeScript. The output is fully static, with no client framework running in the browser. The only client-side JavaScript is a theme toggle and the screenshot lightbox; the rest of the page renders at build time. I built it using Claude Code as part of my development workflow.View the source on GitHub.

What colleagues say

“I've had the pleasure of working with Ciaran over the last 6 years, and he's been an incredibly thoughtful, collaborative, and kind teammate. He played a foundational role in building the mobile app from the ground up, and his contributions have shaped the product in a lasting way.”

Sarah Tong, Senior Product Designer & Web Developer at Guusto

“I'd be more than happy to recommend Ciaran to anyone looking for an exceptional mobile developer. He's not only a talented mobile engineer but also someone who's incredibly communicative, thoughtful, and easy to work with.”

Sreeja Guttula, Junior Product Manager at Guusto

Experience & Education

  1. 2020–2026

    Guusto Gifts Inc.

    Frontend Engineer (Contract, remote)

    Sole React Native developer; see case study. Ended with full technical handover to successor team.

  2. 2019

    AdBusters Media Foundation (contract)

    React Native Developer

    Built the World Revolution app to client + UX team requirements.

  3. 2019

    Fraser Region Aboriginal Friendship Center Association (contract)

    Web Developer

    Custom WordPress theme (PHP, JS animations, SCSS).

  4. 2012–2019

    Independent game developer

    Unity 3D / C#

    Turn-based strategy, FPS, RPG, simulation, puzzle; shipped intuitive controls/menus for iOS, Android, Windows, Web.

Education

  1. 2019

    RED Academy

    Full Stack Development bootcamp

  2. 2013–2015

    BCIT

    Game Development

  3. 2011–2013

    BCIT

    Computer Information Technology

Skills

Core

  • React Native
  • TypeScript
  • JavaScript
  • React

Mobile

  • iOS + Android release management
  • Client-side push notifications
  • Deep links
  • App Store submission & review
  • Figma design handoff

Platform

  • REST API integration
  • Git / Bitbucket
  • Jira

Ways of working

  • AI-assisted development (Claude Code, Codex)
  • Cross-functional + cross-timezone collaboration
  • Technical handover & onboarding

Contact

I'm interviewing for senior React Native roles starting August 2026. Email me.

Resume downloads

CVEnglishPDFDOCX
履歴書RirekishoPDFDOCX
職務経歴書Shokumu keirekishoPDFDOCX