Kai Chen, Full-stack Developer in Fushun, Liaoning, China
Kai Chen

Full-stack Developer in Fushun, Liaoning, China

Member since March 9, 2017
Kai is a highly efficient and reliable professional who possesses wide skills in web and mobile app development. He's worked on many projects with both startups and enterprise companies. He has drive, a positive attitude, and proactive approach helps him deliver high-quality results in a very natural way. In addition to his familiarity with both Agile/Scrum principle, he also focuses on maintaining excellent communication with clients and team members.
Kai is now available for hire




Fushun, Liaoning, China



Preferred Environment

Jira, Slack, Visual Studio Code, Git, Linux, Mac OS

The most amazing...

...project that I've done is a SaaS-based web application to provide white labeling and analytics in the clean energy industry.


  • Senior Full-stack Developer

    2020 - 2020
    Embrk (via Toptal)
    • Fixed the 10+ issues of Ruby on Rails and GraphQL and integrated Apollo Studio in the project.
    • Updated the UI with Angular 9+ in the Shopify eCommerce project.
    • Created the admin panel of a music project based on the InVision and Sketch design using Angular 9, MaterialUI, and Django API.
    Technologies: Prismic, Shopify, Material Design, Apollo, GraphQL, Ruby on Rails (RoR), TypeScript, Angular Universal, Angular Material, Angular
  • Senior Full-stack Developer

    2020 - 2020
    Sunlytix, LLC (via Toptal)
    • Implemented SaaS-based white-labeling apps using React, Redux, and Styled-Components.
    • Developed microservices with AWS Lambda and REST APIs with Django/Python.
    • Integrated many services including validating email/phone number, analytics, geolocation, Google Maps, etc.
    • Deployed the server to AWS Lightsail and AWS S3 and integrated CDN to improve the performance.
    Technologies: React, Google Maps API, AWS Lambda, Styled-components, Styled Components, SCSS, JavaScript, Nginx, AWS EC2, AWS S3, MySQL, Django, Python, React Redux
  • Senior Web Developer

    2019 - 2019
    Thinkful, Inc (via Toptal)
    • Created and converted old pages with new design and Vue.js.
    • Applied best practices and built pixel perfect and responsive designs with Vue.js and LESS.
    • Implemented server-side rendering and SPAs and integrated backend endpoints to fetch the data.
    Technologies: Docker, Jest, JavaScript, Nuxt.js, Less, CSS, Vue.js
  • Mobile App Developer

    2019 - 2019
    Perk Health, LLC (via Toptal)
    • Fixed the authentication issues and visual designs of the current Ionic/Cordova app.
    • Built user management using AWS Cognito and AWS Amplify.
    • Integrated oAuth and OpenID Connect to implement authentication.
    Technologies: SCSS, TypeScript, OpenID, OAuth, AWS Amplify, Amazon Cognito, Cordova, Ionic, Angular
  • Mobile App Developer

    2019 - 2019
    Groebneural, LLC (via Toptal)
    • Reviewed the codebase and refactored clean with best practices.
    • Updated inquiry steps with the correct flow and fixed the UIs to fit with various sizes of screens.
    • Changed the structure of Firebase and updated logic to interact with it.
    Technologies: Mobile, iOS, Android, SCSS, TypeScript, Firebase, Ionic 3, Angular
  • Senior Full-stack Developer

    2018 - 2019
    Tillerman Inc (via Toptal)
    • Implemented the flows of users, market, causes, and user reports using React Native.
    • Integrated mailing service with Sendgrid and SMS service with EZTexting.
    • Integrated Firebase CloudStore to save all information and set up the indices with various keys.
    Technologies: Texting, SendGrid, React Navigation, Redux Thunk, iOS, Android, Redux, Firebase, React Native
  • Senior JavaScript Developer

    2018 - 2019
    Fuel3d Technologies Ltd (via Toptal)
    • Implemented the 3D viewer of eyewear using React and Three.js.
    • Built REST APIs and microservices using Node.js and Express.js.
    • Created a dashboard to upload and save web scan files to AWS S3 and generated analytics with charts.
    • Wrote unit tests using Enzyme and Jest for the front-end part.
    Technologies: AWS S3, Bootstrap, CSS3, HTML5, Express.js, Node.js, Redux, React, Three.js, JavaScript
  • Mobile Developer

    2018 - 2018
    Smex (via Toptal)
    • Implemented navigation and structure of mobile apps using React Native.
    • Converted the Sketch designs to cross-device/platform pages.
    • Implemented data visualization with banking transaction analysis.
    Technologies: Highcharts, iOS, Android, Redux, React Native, React
  • Full-stack Developer

    2017 - 2018
    Granular Data (via Toptal)
    • Implemented an interface within the dashboard to display graphs/charts with DC.js and Crossfilter.
    • Displayed geographical maps and interactive tables using Leaflet.js and AG-Table.
    • Created an admin dashboard using CoreUI, React, and Apache Superset.
    • Integrated back-end APIs and third-party services like News and Stripe.
    Technologies: D3.js, Data Visualization, Dashboard Design, Crossfilter, Redux, React, JavaScript, Flask, Python
  • Mobile Developer

    2017 - 2017
    • Created a hybrid mobile app from scratch for Android and iOS.
    • Designed and implemented business logic in an Ionic and Cordova project with best practices.
    • Deployed apps to production fro Android and iOS using Apple Store and Google Play Store.
    • Implemented push notifications, keyboard, geolocation, and contacts.
    • Integrated third-party services like Facebook, Google Maps, and Instagram.
    Technologies: Amazon Web Services (AWS), PubNub, JavaScript, AWS, Google Material Design, Firebase, Angular, Cordova, Ionic
  • Senior JavaScript Developer

    2016 - 2017
    • Created the product customizer using D3.js, Three.js, and JavaScript.
    • Created the RESTful APIs to fetch the recipes and attributes for customizer using Node.js, Express.js, and MongoDB.
    • Implemented the logic for editing live product and the functionality of exporting/importing.
    • Created the admin portal to manage the products and templates using React.js and Bootstrap.
    Technologies: MongoDB, Express.js, Webpack, JavaScript, Three.js, D3.js, WebGL, Node.js
  • Front-end Developer

    2015 - 2017
    • Developed a React/Redux app from conception to completion.
    • Created the app structure including the front-end code base, API proxy and server, deployment pipeline, and continuous integration.
    • Translated and/or reused components from a prototype version which was based on the Middleman JS framework.
    • Implemented robust solutions and best practices to all aspects of the app, from UI/UX to API communication and authentication.
    Technologies: CSS3, HTML5, SCSS, Babel, Webpack, JavaScript, JSX, ECMAScript (ES6), Redux, React
  • Full-stack Developer

    2014 - 2015
    • Implemented a mobile app development framework based on Ionic and AngularJS.
    • Created a mobile app builder and CMS.
    • Integrated with third party services like PhoneGap Build, Google Maps, and Pushwoosh.
    • Designed an app experience that can be changed in real time via SaaS-based CMS.
    • Deployed mobile apps to App Store and Google Play.
    Technologies: MySQL, JSON, PHP, JavaScript, Google Maps, Pushwoosh, PhoneGap, Ionic, AngularJS
  • Web Developer

    2013 - 2014
    • Created a learning management system that allows users to purchase individual/private courses, subscribe to multi-level courses, play the quiz, and learn with teachers. Implemented online meeting, quiz levels, and badge functionality.
    • Developed the user interface and integrated the back-end with many third parties including Active Campaign, Stripe, Tripletex, Adobe Connect, and more.
    Technologies: React, Bitbucket, Node.js, Ionic, AngularJS, Bootstrap, Stripe, PostgreSQL, Ruby on Rails (RoR), Ruby
  • Web Developer

    2012 - 2013
    • Developed a web application for users to upload and purchase music and sound files, and integrated payment methods including Paypal, Stripe, and WeChat.
    • Created a web-based custom music player with multi-language support and a custom admin dashboard.
    Technologies: CSS3, HTML5, PostgreSQL, Ruby on Rails (RoR), Ruby, Git, Stripe, AngularJS, Bootstrap, JavaScript, MySQL, PHP


  • Demand IQ (Development)

    Demand IQ is the all-in-one toolkit and advertising platform for effective customer acquisition. Demand IQ brings together best in class advertising with our proprietary software technology that helps consumers more effectively shop for renewable energy products and services online.
    I implemented the white labeling app that is available to config per clients to get an estimation of energy savings.

  • PRISM App (Development)

    PRISM is an application that enhances the quality of clinical discussion between healthcare providers and patients by allowing for continued patient engagement outside of the clinical setting.
    PRISM enables patients to complete physical function and other PROMIS measures through an easy-to-use app with features including score trending, peer group comparisons, and relevant recommendations.

  • MavelOptics (Development)

    I created an eCommerce platform that provides quality eye-wear at an affordable price. Built with Python, Django, AngularJS, and JavaScript. Supported many payment gateways like credit card, Paypal, Stripe, and Wire Bank.

  • AdeptLMS (Development)

    I created the learning management system that allows users to purchase individual/private courses, subscribe to multi-level courses, play the quiz, and learn with teachers. Implemented online meetings, quiz levels, and badge functionality.
    I also developed the user interface using React and Bootstrap, and integrated with many third parties including Active Campaign, Stripe, Tripletex, Adobe Connect, and more.


  • Languages

    HTML5, CSS3, TypeScript, HTML, CSS, SCSS, Go, Python, JavaScript, Ruby, PHP, GraphQL, ECMAScript (ES6), Less
  • Frameworks

    Bootstrap 4, Next.js, Express.js, Angular, Ionic 2, Ionic, React Native, Ruby on Rails (RoR), Angular Material, Laravel, CodeIgniter, Vuetify.js, Electron.js, Cordova, Django, Nuxt.js, Bootstrap, Laravel 5, Redux, Ionic 3, AngularJS, PhoneGap, Flask, Jest
  • Libraries/APIs

    Styled-components, Google Maps API, React, Vue.js, Vue.js 2, Vuex, AngularUI, Stripe, Redux-saga, React Redux, Node.js, WebGL, D3.js, Three.js, Pushwoosh, Google Maps, PubNub, Crossfilter, Highcharts, React Navigation, AWS Amplify, OpenID
  • Tools

    Nginx, Slack, Angular Universal, Redux Thunk, Webpack, Babel, Jira, Git, Vue CLI, Webpack 4, Bitbucket, JSX, SendGrid, Amazon Cognito
  • Platforms

    AWS Lambda, Mac OS, Linux, Visual Studio Code, Heroku, Firebase, iOS, Amazon Web Services (AWS), Shopify, AWS EC2, DigitalOcean, Android, Twilio, Mobile, Docker
  • Storage

    AWS S3, PostgreSQL, MySQL, MongoDB, JSON
  • Other

    Styled Components, Material Design, Apps, Full-stack, Hybrid Apps, Mobile App Development, PWA, AWS, Apollo, Prismic, Google Material Design, Dashboard Design, Data Visualization, Texting, OAuth
  • Paradigms

    Scrum, Agile Software Development


  • Bachelor of Computer Science degree in Computer Engineering
    2008 - 2012
    Shanghai Jiaotong University - Shanghai, China

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