- Introduced backend framework Nest.js and ORM framework Prisma.js - Designed main service backend db schema and testing tools - Maintain system, env setup document - Designed and implement inbound and packing process in fulfillment system by using express.js and sequelize.js - Built Class-level logging decorator for distributed logging under microservice - Built Transaction decorator by using JS proxy and continuation-local storage - Initiated CI/CD flow for Nest.js based microservice - Developed testing and deploy config on CircleCI - Configured K8s setting and docker images for new services - Participated tech sharing session as main speaker for unix system and linux kernel - Implemented API integration with 3rd party services from vendors and customers - Proposed new workflows for i18n development and dependencies upgrade - Implemented job queue on app - Implemented admin features by React.js and Material UI - Implemented deliver agent features by React Native

- Solved server system incompatible errors and reduced hot reload and build time by upgrading main frontend framework Nuxt.js version - Refactored i18n system and reduced page loading time - Standardized develop env and built conversation between TypeScript to JavaScript for frontend language transition - Refactored SSR pages and reduce server loading - Reduced statice resource number and move it to CDN - Developed a dashboard and integrated with backend API - Built product displaying features by using Vue 2, pug and sass