Introduction
Work Experience
Education
Technical skills
Fremont, CA
English
Mandarin
Guanggeng is a Fremont-based Senior Software Engineer with a passion for building scalable web applications and leading technical migrations. His expertise includes end-to-end rearchitecture of medical e-commerce platforms, migrating from legacy Vue 2 stacks to Next.js/React.js, and achieving significant performance improvements. With a strong background in both frontend and mobile development, he has successfully improved GTmetrix Performance Grade from D to A, reduced LCP by 3.1s to 1.2s, and boosted mobile conversion rates by 22%. His approach combines technical excellence with leadership skills, having led 3-person teams in agile environments while implementing robust testing strategies and establishing SEO-optimized architectures.
Work Experience
Vibrant WellnessSenior Software Engineer
Jul 2021 - Present- Led the end-to-end rearchitecture of a medical e-commerce platform, migrating from a legacy Vue 2 stack to Next.js/React.js, addressing critical issues in build performance, SEO limitations, and UI scalability and atomic design.
- Improved performance through Next.js SSR/SSG implementation, boosting GTmetrix Performance Grade from D to A, reducing LCP from 3.1s to 1.2s, Fully Loaded Time from 8.4s to 1.3s, page size by 85%, and HTTP requests by 60%, resulting in faster page interaction and seamless browsing.
- Established SEO-optimized architecture using SSR, semantic HTML, and metadata. Elevated Lighthouse SEO scores from 67 to 100 by resolving missing meta descriptions, alt attributes, and crawlability issues, significantly enhancing discoverability with projected organic visibility uplift of 30-40%.
- Developed and executed a robust frontend testing strategy tailored for a high-traffic e-commerce platform. Used Jest for unit testing key business logic, with Vitest, and Playwright for automated end-to-end flows (login, checkout, search). Achieved 85%+ test coverage and cut production issues by 40%.
- Utilized web and data analytics tools including Google Analytics, Mixpanel, and Sentry to systematically track user behavior, feature adoption, and overall stabilization metrics. Improved user experience and guided performance adjustments, resulting in a 25% increase in conversion rate and a 15% reduction in bounce rate. Used Sentry to proactively resolve runtime issues, reducing frontend error rates by 35%.
- Designed and built a modular, reusable UI component library using Tailwind CSS and shadcn/ui, ensuring consistency, scalability, and fast iteration. Worked closely with designers to deliver pixel-perfect interfaces and cohesive user experience.
- Supported responsive design by implementing adaptive layouts and touch-friendly components to fit all screen sizes, resulting in a 22% increase in mobile conversion. Added accessibility enhancements such as semantic HTML, ARIA roles, and keyboard navigation to improve usability and meet WCAG 2.1 guidelines.
- Collaborated with product managers and backend engineers to define clear, actionable development goals and streamline communication. Utilized Jira and Confluence to track progress and align API implementation with business priorities and frontend needs, ensuring well-timed scope and deliverables and strict deadlines.
- Acted as frontend tech lead, leading a 3-person team in an agile environment, overseeing end-to-end frontend design, sprint-based feature delivery, and ongoing performance optimization. Drove key architectural decisions aligned with agile principles, implemented scalable engineering solutions (hydration optimization, lazy loading, route-based code splitting), and enforced code quality via ESLint and Prettier. Documented architecture decisions and coding standards; promoted team alignment and code quality through pair programming and shared learning.
Alexander-Anderson Real Estate GroupSoftware Engineer
Oct 2020 - Sep 2022- Independently designed and developed a cross-platform mobile app (CFREE Real Estate Exam Prep) for real estate professionals using React Native and Expo. Released to Google Play and the App Store, achieving 100+ users and positive feedback for usability and practical value.
- Developed high-performance UI components using UI Kitten 5, applying custom theming and responsive layout techniques to support consistent UX across devices.
- Implemented key mobile features including In-App Purchases, Push Notifications, and Firebase Authentication, enabling secure user engagement and subscription-based access using React Navigation and local state management with AsyncStorage.
KALO Inc.Software Engineer
Feb 2020 - Oct 2022- Built a responsive, single-page marketing dashboard using React.js, Redux, and Material UI. Enhanced mobile usability and reduced page load time to optimize component rendering.
- Deployed the application and Node.js-based API server on Heroku with automated deployment pipelines. Configured environment variables and logging strategies to support staging and production workflows and facilitate easier debugging and release cycles.
Education
Pace University, Seidenberg School of Computer Science and Information SystemsMaster of Science in Computer Science - GPA 3.8
Human University of Chinese MedicineBachelor of Engineering in Biology - GPA 3.5
Technical skills
Programming LanguagesJavaScript, TypeScript, Node.js, HTML5, CSS3, Java, Python, SQL, PHP
Frameworks & LibrariesReact.js, Vue.js, Angular, React Native, Redux, Next.js
Tools & OthersExpress, RESTful APIs, Jest, Tailwind CSS, Mixpanel, Google Analytics 4, Sentry, Playwright