
Kevin Wang
Senior Full Stack Engineer | Next.js, React
Salaire / Taux journalier
Florida, État de New York, États-Unis
Freelance
Expertises
À propos
Introduction
Full-stack engineer with 4+ years building scalable web platforms across fintech, e-commerce, and SaaS. Led end-to-end development of booking platforms and headless commerce sites using Next.js, React, and Node.js—reducing bundle size, improving performance by 70%, and integrating Stripe, PayPal, and blockchain payments. Specialized in modern architecture, performance optimization, and delivering production-ready solutions that drive growth.
Expérience de travail
CoachUp, Inc
déc. 2024 - avr. 2026
1 an 5 mois
Florida, État de New York, États-Unis
Lead Full-Stack Engineer
déc. 2024 - avr. 2026
1 an 5 mois
Florida, État de New York, États-Unis
– Designed and built the entire trainer booking platform end-to-end, including authentication, booking flows, trainer profiles, messaging, and session management. – Developed a clean, scalable architecture using Next.js, React, Node.js, and modern API patterns. – Reduced frontend bundle size and improved performance by replacing heavy dependencies like Redux with TanStack React Query and Zustand, modernizing form handling with React Hook Form + Zod, and implementing code-splitting, lazy loading, and optimized builds using Next.js, Webpack Analyzer, and Turbopack. – Implemented media upload pipelines using AWS S3, including secure file handling, pre-signed URLs, and optimized storage/access patterns for images and videos. – Integrated global payment and communication systems, including PayPal, Stripe, Mailgun, and automated email flows. – Implemented analytics and growth tools (GA4, tracking funnels, user behavior insights) to support marketing and onboarding. – Optimized performance and SEO, improving load times, Core Web Vitals, and organic discoverability. – Collaborated with trainers, athletes, and early adopters to refine features and improve user experience.
Lead Full-Stack Engineer
déc. 2024 - avr. 2026
1 an 5 mois
Florida, État de New York, États-Unis
– Designed and built the entire trainer booking platform end-to-end, including authentication, booking flows, trainer profiles, messaging, and session management. – Developed a clean, scalable architecture using Next.js, React, Node.js, and modern API patterns. – Reduced frontend bundle size and improved performance by replacing heavy dependencies like Redux with TanStack React Query and Zustand, modernizing form handling with React Hook Form + Zod, and implementing code-splitting, lazy loading, and optimized builds using Next.js, Webpack Analyzer, and Turbopack. – Implemented media upload pipelines using AWS S3, including secure file handling, pre-signed URLs, and optimized storage/access patterns for images and videos. – Integrated global payment and communication systems, including PayPal, Stripe, Mailgun, and automated email flows. – Implemented analytics and growth tools (GA4, tracking funnels, user behavior insights) to support marketing and onboarding.
Texas MattressMakers
févr. 2023 - nov. 2024
1 an 10 mois
Texas, GA 30217, États-Unis
Full Stack Developer
févr. 2023 - nov. 2024
1 an 10 mois
Texas, GA 30217, États-Unis
– Developed a fully headless e-commerce experience by integrating WordPress + WooCommerce APIs with a custom Next.js frontend, improving performance, scalability, and maintainability. – Modeled structured content using Advanced Custom Fields (ACF) and Custom Post Types (CPT) to define flexible schemas, enabling reusable, component-driven content delivery across the frontend. – Implemented secure Stripe payment processing, including checkout flows, server-side validation, and webhook handling for order confirmation and fulfillment. – Converted Figma designs into pixel-perfect, mobile-responsive UI, ensuring consistent branding and flawless user experience across all devices. – Optimized API communication between the WordPress backend and the Next.js frontend, improving data fetching, caching, and overall site performance. – Customized WooCommerce endpoints to support advanced product logic, dynamic pricing, and real-time inventory updates. – Collaborated with designers and stakeholders to refine UX, streamline user flows, and deliver a high-quality, production-ready headless storefront. – Improved SEO and Core Web Vitals through optimized rendering, image handling, and performance tuning in Next.js.
Full Stack Developer
févr. 2023 - nov. 2024
1 an 10 mois
Texas, GA 30217, États-Unis
– Developed a fully headless e-commerce experience by integrating WordPress + WooCommerce APIs with a custom Next.js frontend, improving performance, scalability, and maintainability. – Modeled structured content using Advanced Custom Fields (ACF) and Custom Post Types (CPT) to define flexible schemas, enabling reusable, component-driven content delivery across the frontend. – Implemented secure Stripe payment processing, including checkout flows, server-side validation, and webhook handling for order confirmation and fulfillment. – Converted Figma designs into pixel-perfect, mobile-responsive UI, ensuring consistent branding and flawless user experience across all devices. – Optimized API communication between the WordPress backend and the Next.js frontend, improving data fetching, caching, and overall site performance. – Customized WooCommerce endpoints to support advanced product logic, dynamic pricing, and real-time inventory updates. – Collaborated with designers and stakeholders to refine UX, streamline user flows, and deliver a high-quality, production-ready headless storefront. – Improved SEO and Core Web Vitals through optimized rendering, image handling, and performance tuning in Next.js.
Fairmint
janv. 2022 - janv. 2023
1 an 1 mois
Houston, Texas, États-Unis
Frontend Developer
janv. 2022 - janv. 2023
1 an 1 mois
Houston, Texas, États-Unis
– Led the end-to-end development of Fairmint.com, building a modular React + TypeScript frontend and a Node.js (Express) backend integrated with Hygraph 4 GraphQL APIs for dynamic content delivery and Stripe for secure checkout. – Architected dual payment infrastructure supporting both fiat (ACH/wire) and on-chain stablecoin transactions (USDC/USDT), including wallet integration, transaction signing, blockchain event/listener handling, and real-time settlement verification synchronized with backend investment and cap table systems. – Built UI and data flows supporting cap table management, enabling separation of large VC investments and aggregation (“roll-up”) of smaller investors into a single entity entry. – Enhanced UX and performance through responsive design, code-splitting, lazy loading, and image optimization, ensuring fast load times across all devices. – Implemented secure checkout and order-processing workflows with robust API error handling, data validation, and reliability improvements for transaction flows. – Collaborated closely with designers, QA engineers, and stakeholders in Agile sprints; documented technical decisions and supported deployment, monitoring, and ongoing maintenance.
Frontend Developer
janv. 2022 - janv. 2023
1 an 1 mois
Houston, Texas, États-Unis
– Led the end-to-end development of Fairmint.com, building a modular React + TypeScript frontend and a Node.js (Express) backend integrated with Hygraph 4 GraphQL APIs for dynamic content delivery and Stripe for secure checkout. – Architected dual payment infrastructure supporting both fiat (ACH/wire) and on-chain stablecoin transactions (USDC/USDT), including wallet integration, transaction signing, blockchain event/listener handling, and real-time settlement verification synchronized with backend investment and cap table systems. – Built UI and data flows supporting cap table management, enabling separation of large VC investments and aggregation (“roll-up”) of smaller investors into a single entity entry. – Enhanced UX and performance through responsive design, code-splitting, lazy loading, and image optimization, ensuring fast load times across all devices. – Implemented secure checkout and order-processing workflows with robust API error handling, data validation, and reliability improvements for transaction flows. – Collaborated closely with designers, QA engineers, and stakeholders in Agile sprints; documented technical decisions and supported deployment, monitoring, and ongoing maintenance.
OPSWAT
janv. 2021 - janv. 2022
1 an 1 mois
Florida, État de New York, États-Unis
Software Developer
janv. 2021 - janv. 2022
1 an 1 mois
Florida, État de New York, États-Unis
– Maintained and enhanced Linux MetaDefender Kiosk web applications using React, TypeScript, Redux Toolkit, and WebSocket to support mitigating removable media threats. – Developed a React web application for modifying kiosk settings, improving data integrity through advanced validation with React-Hook-Form and custom regex patterns. – Designed cross-document messaging (postMessage) to facilitate communication between the management site and the product iframe, ensuring framework agnostic integration across teams. – Reduced UI-reported bugs by 50% by migrating select projects to TypeScript and implementing 300 unit tests with Jest and React Testing Library. – Built media file selector and scan details features, optimizing performance and reducing memory usage by 70% compared to previous versions by utilizing virtualized lists. – Improved TeamCity CI/CD pipeline build times by 10% with NPM workspaces. – Decreased bundle sizes by 12% through the migration of component library build tools to Rollup.js.
Software Developer
janv. 2021 - janv. 2022
1 an 1 mois
Florida, État de New York, États-Unis
– Maintained and enhanced Linux MetaDefender Kiosk web applications using React, TypeScript, Redux Toolkit, and WebSocket to support mitigating removable media threats. – Developed a React web application for modifying kiosk settings, improving data integrity through advanced validation with React-Hook-Form and custom regex patterns. – Designed cross-document messaging (postMessage) to facilitate communication between the management site and the product iframe, ensuring framework agnostic integration across teams. – Reduced UI-reported bugs by 50% by migrating select projects to TypeScript and implementing 300 unit tests with Jest and React Testing Library. – Built media file selector and scan details features, optimizing performance and reducing memory usage by 70% compared to previous versions by utilizing virtualized lists. – Improved TeamCity CI/CD pipeline build times by 10% with NPM workspaces. – Decreased bundle sizes by 12% through the migration of component library build tools to Rollup.js.
Formation
University of Florida
Bachelor, Computer Science
2016 - 2020
4 ans 5 mois
University of Florida
Bachelor, Computer Science
2016 - 2020
4 ans 5 mois