I build Flutter applications that ship to production and stay there. 6+ years across four demanding domains — email clients (JMAP protocol, multi-platform sync), financial platforms (KYC, investment flows, encrypted data), Web3 (wallet integration, real-time on-chain data), and Matrix-based communication (federated real-time chat, push rules, end-to-end encrypted messaging) — plus e-commerce at scale.

Currently contributing to open source at Linagora. My focus is on the hard parts: system design under real constraints, complex media pipelines, real-time sync, and shipping features that hold up in production.

Design scalable mobile systems — When a feature has ambiguous scope or hidden complexity, I define the architecture before writing a line of code. I break down sync conflicts, background processing constraints, and permission models into decisions that can be documented, reviewed, and changed safely. I write ADRs, lead grooming sessions, and treat upfront design as part of delivery — not an afterthought.

Solve hard product problems end-to-end — Real-time sync with deduplication edge cases. Media pipelines that need to work offline and on low-end hardware. Permission systems with complex state transitions. I've shipped these across fintech, communication, and Web3 products — and the pattern is always the same: understand the failure modes first, then design around them.

Eliminate performance problems others avoid — Frame profiling, heap snapshots, widget rebuild auditing, image cache tuning. I've taken janky screens down to 60fps on low-end devices, tracked memory leaks to their source, and improved scroll performance on heavy list views. I profile first, then fix — not the other way around.

Own delivery and production reliability — Full CI/CD pipeline ownership (Bitrise, Fastlane, GitHub Actions), iOS signing, Android keystore, App Store + Play Store delivery. Post-ship, I maintain a Sentry monitoring discipline: no issue stays unresolved beyond a week, store issues reviewed weekly, new errors opened immediately.

Test what actually ships — E2E coverage with Patrol on real devices including WebView SSO flows. Unit, widget, and integration tests enforced per PR. I've worked with AI-assisted debugging and testing, and I'm actively bootstrapping E2E coverage for web with nightly CI runs.

Integrate and debug complex third-party services — I've connected fintech platforms (KYC, payment), push infrastructure (APNs, FCM), analytics and engagement services, Web3 wallets, and authentication providers. When integrations break in production, I debug at the protocol level — not just swap SDKs.

Active contributor across Flutter apps with 1,400+ combined GitHub stars

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Open to open-source collaboration — nqhh.dev@gmail.com