Impact
Card economics on one screen
Built the first layer of a four-layer card P&L dashboard — the foundation the other three layers report from.
The only line here that reads as profit and loss rather than features.
Hong Kong · Android · Fintech & Digital Assets
I'm Derek Yu, a senior Android developer with over 10 years delivering mobile money products in Hong Kong — from a tier-1 bank's flagship personal banking app to the consumer app at Crypto.com.
Senior Android Developer on the Crypto.com consumer app, across fiat and card surfaces.
Crypto.com. Fiat and card journeys, regulatory features, production monitoring and incident response.
Chinasoft International. Built and maintained the bank's flagship personal banking app: account opening, FPS transfers, mobile cheque deposit, cardless ATM, biometric login.
Lalamove. Driver app features used by delivery riders across Asia in real time.
JETCO. P2P payment apps for Hong Kong and Macau, plus eKYC and authentication SDKs.
HSBC HK Easy Invest, property and community apps, and React Native work from its early days.
Impact
Built the first layer of a four-layer card P&L dashboard — the foundation the other three layers report from.
The only line here that reads as profit and loss rather than features.
Reliability
Built Datadog and real-user-monitoring dashboards for production card API health across Android, iOS and React Native, with a card-region attribute instrumented on all three, so triage starts from a dashboard rather than a guess.
Named first-line responder for P0 incidents across mobile and web.
Compliance
Led multi-region rollout of transfer-compliance features end to end — front-end feasibility, user-facing flows and release handover.
Where a wrong default becomes a regulatory incident, the detail is the product.
Craft
Authored an internal knowledge base that compresses years of legacy Android context into something the new stack can act on, and documented the card-application flow for several markets.
Also coordinates staging builds and merge-to-release.
Native Cantonese · fluent English & Mandarin · HKU SPACE Postgraduate Diploma in IT
Open to conversations about Android, React Native and regulated money movement.