Trung Ly

PWA mobile POS for fast draft orders, enabling quicker order creation and improving customer checkout speed by ~20%.

Designed and implemented scalable, maintainable architecture for mobile POS app.

Managed app data and state using Context API; handled API requests with Axios.

Developed styled UI with Tailwind CSS, improving usability on mobile devices.

Contributed ideas and technology improvements to enhance user experience.

Monitored app performance and usage via Sentry, Microsoft Clarity, and Feedback, enabling data-driven optimizations.

Delivered as a PWA, allowing offline usage and faster access on mobile devices.

Retail POS system for 200+ stores in Vietnam and 30+ stores in Cambodia, supporting core sales operations including product scanning, payment processing (cash, card, QR code), order management, inventory tracking, revenue reporting, promotions, refunds, and detailed sales analytics for business decisions.

Refactored legacy codebase into a clean, modular architecture, reducing redundant code by ~35% and improving readability and maintainability.

Optimized order flow, creating orders ~25% faster.

Improved performance for inventory, payments, and reporting for reliable real-time data.

Simplified complex business logic, making the system more scalable for future feature expansion.

Collaborated with backend, QA, ops, and store teams to align business logic, ensure smooth feature integration, and maintain consistent UI/UX.

Self Checkout system providing time savings, improved convenience, enhanced information security, reduced staff workload, and a modern shopping experience.

Designed and implemented scalable, maintainable project architecture, standardizing modules and enabling code reuse, reducing development time by ~30%.

Managed app data and state using Context API, and handled data fetching with Axios.

Developed responsive UI using Tailwind CSS, enhancing user experience and reducing user errors by ~25%.

Integrated printing solutions, enabling direct receipt and document printing.

Replaced traditional barcode scanning with RFID technology, improving product scanning speed by 40% and accuracy by 30%.

Contributed ideas to enhance app features, optimize tech stack, and streamline workflows.

Monitored, analyzed, and reported app performance and crashes via Sentry, reducing downtime to <1%.

Delivered the project at 50% lower cost than prior provider.

Developed Zalo Mini Apps for multiple retail brands

Designed and implemented scalable, reusable architecture for multiple Zalo Mini Apps, improving maintainability and reducing development time for new brand apps.

Developed applications using Zalo APIs, integrating backend services and managing state with Zustand and Axios.

Refactored and reviewed code to enhance performance, scalability, and readability.

Mentored junior developers, improving code quality and team productivity.

Implemented CI/CD pipelines for automated build and deployment, improving release efficiency.

ONWAYS Rewards : https://zalo.me/s/957354804063278119

MARC Rewards : https://zalo.me/s/3920331891151869531

Pepsico Foods : https://zalo.me/s/2285472306095214609

E-commerce apps built with React Native Expo, serving 100k+ active users across multiple brands, supporting shopping, notifications, analytics, and seamless user experience.

Migrated and upgraded multiple codebases from React Native CLI to Expo CLI, streamlining workflows and reducing build & release time by ~30%.

Designed and implemented scalable, reusable architectures, improving maintainability and supporting simultaneous development of 7+ brand apps.

Managed app data and state with API integration, AsyncStorage, Redux, Redux-Saga, Redux Toolkit, handling thousands of requests per minute.

Integrated third-party libraries/services: Facebook, Google, CodePush, React-Native-Insider, Firebase Analytics, Sentry, enhancing features, tracking, and reducing crash rate to <1%.

Applied React Navigation for routing, managed notifications through Firebase / Expo Notifications, and deployed apps using native build tools and CI/CD pipelines, speeding up releases by ~25%.

Collaborated with cross-functional teams to deliver consistent UI/UX, optimized performance, and e-commerce experiences across brands.

Monitored, analyzed, and reported app metrics to drive continuous improvement and maintain high app stability and user retention.

Training and Learning

Gained proficiency in JavaScript, ES6, and React Native API.

Learned React Native components, API integration, debugging, and app deployment.

Studied and implemented efficient source code structures.