Kai Chen, Developer in Fushun, Liaoning, China
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Kai Chen

Verified Expert  in Engineering

Full-stack Developer

Location
Fushun, Liaoning, China
Toptal Member Since
August 11, 2017

Kai is a highly efficient and reliable professional who possesses a wide range of skills in web and mobile app development. He has worked on many projects with both startups and enterprise companies. Kai has drive, a positive attitude, and proactive approach that help him deliver high-quality results in a very natural way. In addition to his familiarity with both Agile and Scrum principles, Kai also focuses on maintaining excellent communication with clients and team members.

Portfolio

Embrk (via Toptal)
Prismic, Shopify, Material Design, Apollo, GraphQL, Ruby on Rails (RoR)...
Sunlytix, LLC (via Toptal)
React, Google Maps API, AWS Lambda, Styled-components, SCSS, JavaScript, NGINX...
Thinkful, Inc (via Toptal)
Docker, Jest, JavaScript, Nuxt.js, Less, CSS, Vue, Unit Testing

Experience

Availability

Part-time

Preferred Environment

Jira, Slack, Visual Studio Code (VS Code), Git, Linux, MacOS

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.

Work Experience

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, Material-UI, and Django API.
Technologies: Prismic, Shopify, Material Design, Apollo, GraphQL, Ruby on Rails (RoR), TypeScript, Angular Universal, Angular Material, Angular, Next.js, Unit Testing, Material UI

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 numerous services, including validating email and phone numbers, analytics, geolocation, Google Maps, among others.
  • 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, SCSS, JavaScript, NGINX, Amazon EC2, Amazon S3 (AWS S3), MySQL, Django, Python, React Redux, Redux RTK, Redux, Unit Testing

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 back-end endpoints to fetch the data.
Technologies: Docker, Jest, JavaScript, Nuxt.js, Less, CSS, Vue, Unit Testing

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 the mailing service with SendGrid and the SMS service with EZ Texting.
  • Integrated Firebase CloudStore to save all information and set up the indices with various keys.
  • Created microservices to generate the reports using Go.
Technologies: Texting, SendGrid, React Navigation, Redux Thunk, iOS, Android, Redux, Firebase, React Native, Go

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: Amazon S3 (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
Self-employed
  • 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 for 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, Google Material Design, Firebase, Angular, Cordova, Ionic

Senior JavaScript Developer

2016 - 2017
Self-employed
  • 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 the live product and the functionality of exporting and 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
FlexFunds
  • 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
FitnessLabs
  • 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
AdeptLMS
  • 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: Bitbucket, Node.js, Ionic, AngularJS, Bootstrap, Stripe, React, PostgreSQL, Ruby on Rails (RoR), Ruby

Web Developer

2012 - 2013
101Music
  • 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

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

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

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

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

Next.js, Express.js, Material UI, Ant Design, Angular, Ionic 2, Ionic, React Native, Ruby on Rails (RoR), Angular Material, Laravel, CodeIgniter, Vuetify, Electron, Ruby on Rails 5, Django, Nuxt.js, Bootstrap, Laravel 5, Redux, Ionic 3, AngularJS, PhoneGap, Flask, Jest

Libraries/APIs

Google Maps API, Reactstrap, React, Vue, Vue 2, Vuex, AngularUI, Stripe, Redux-Saga, React Redux, Node.js, REST APIs, 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

Paradigms

Unit Testing, Scrum, Agile Software Development

Platforms

AWS Lambda, MacOS, Linux, Visual Studio Code (VS Code), Heroku, Firebase, iOS, Amazon Web Services (AWS), Shopify, Amazon EC2, DigitalOcean, Android, Twilio, Mobile, Docker

Storage

Amazon S3 (AWS S3), PostgreSQL, MySQL, MongoDB, JSON

Other

Styled-components, Material Design, Front-end, User Interface (UI), Apps, Full-stack, Cordova, Hybrid Apps, Mobile App Development, PWA, Apollo, Prismic, Progressive Web Applications (PWA), Redux RTK, Google Material Design, Dashboard Design, Data Visualization, Texting, OAuth

2008 - 2012

Bachelor of Computer Science Degree in Computer Engineering

Shanghai Jiaotong University - Shanghai, China

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