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Product / FinTech

A B2C fintech platform where users earn back their trading fees. We pulled the whole product in-house, web and mobile, and rebuilt it around speed.

Role
Frontend (Web · Mobile)
Timeline
2024 - Present
Platform
Web + iOS / Android
Next.jsTypeScriptReact Native

Overview

Volume traded
$17B+
Paid back to users
$2.2M+
Active users
100K+

The problem

2024 · Inherited from the agency
×Outsourced×Template-built×Web only×No app×No SEO×Agency-gated
Then, in-house

We moved fast and solved the dependency problem, then created a performance one of our own.

~2MB
JS bundle
2-3s
Cold starts

The approach

Routing
App Router

SEO and per-route cache control, without an agency in the loop.

Mobile
RN + WebView hybrid

Native where interaction matters, WebView where content changes weekly, at ~90% shared code.

Observability
Sentry + Mixpanel

Wired in from day one, so “it feels slow” became a number we could move.

The result

measured vs. our own v1

Measured against our own v1, not the agency build. Two years of ownership: shipped in 2024, rebranded and overhauled across 2025-26.

In-app screen load
2-3s<0.5s
JS bundle
~2MB200-300KB
2024Moved in-house · App Router + RN app
2025-26Rebrand + performance overhaul
My role

Drove the core of both phases: the 2024 migration (App Router, the RN app) and the recent rebrand + performance overhaul, while the team of 3-4 handled product work in parallel. Set up the CI/CD and code-review standards still in use.

Tradeoffs

Aggressive caching vs. real-time trading data: static cached at the edge, price and balance bypass. Heavier requests, accepted only where staleness costs users money.

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