Chao Lin, Developer in Tianjin, China

Chao Lin

Software Developer

Tianjin, China
Toptal Member Since
March 1, 2019

With over 12 years of experience in software engineering, Chao is a senior full-stack developer specializing in JavaScript, TypeScript, React, and Node.js. He has completed many projects, including leading an engineering team to build an event management platform that has reached tens of thousands of users. He is a warrior, passionate about finding the best path to get things done. Chao is a perfect resource to help convert your idea into a working product.

Chao is available for hire
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Agile, React Native, Relay, GraphQL, Card Payments
JavaScript, React Native, React, Electron, Laravel, Figma, Agile
Clorox Software Development Group
HTML, SCSS, Git, SQL, Redux, Scrum, Agile, CSS, Amazon S3 (AWS S3), Redux-Saga...


Tianjin, China



Preferred Environment

Microservices, Visual Studio Code (VS Code), MacOS, Amazon Web Services (AWS), Agile, Jira, Slack

The most amazing...

...experience I've had was working for a food delivery startup where I built MVP mobile and web apps that are used by tens of thousands of users.

Work Experience

2021 - 2022

Senior Mobile Developer

  • Developed a banking app that allows US-based clients to create and issue cards that are accepted by most ATMs.
  • Designed and built the mobile app from scratch using React Native.
  • Integrated GraphQL API using relay and defined types for all schemas and models.
Technologies: Agile, React Native, Relay, GraphQL, Card Payments
2020 - 2021

Mobile Developer

  • Rebuilt a mobile app for an emergency management system using React Native.
  • Participated in product design meetings with clients.
  • Reviewed code written by peers and adopted best practices in version control.
Technologies: JavaScript, React Native, React, Electron, Laravel, Figma, Agile
2020 - 2020

Front-end Developer

Clorox Software Development Group
  • Refactored the React components UI from a given Sketch design.
  • Integrated and tested a C# back-end API on the front end.
  • Oversaw the build process of the entire project that requires specific conditions like the Windows platform.
  • Created new components such as Revolutionary Slider using React.
  • Wrote unit tests using Jest and ensured 80% test coverage over the entire project.
Technologies: HTML, SCSS, Git, SQL, Redux, Scrum, Agile, CSS, Amazon S3 (AWS S3), Redux-Saga, Amazon EC2, .NET, React, ECMAScript (ES6), JavaScript
2018 - 2020

Front-end Developer

  • Developed the front end using Vue.js and TypeScript based on a Sketch design.
  • Fixed UI issues in different screen sizes to make it responsive.
  • Integrated GraphQL API (queries and mutations) that were deployed on AWS Amplify.
  • Worked with a seasoned agile team that was made up of experts in all areas including front end, back end, and DevOps.
Technologies: HTML, Apollo, SCSS, Git, Test-driven Development (TDD), Jest, TypeScript, Agile, CSS, Firebase, Vuex, GraphQL, Vue, JavaScript
2019 - 2019

Lead Developer

Atlas Mental Health
  • Refactored the existing codebase to the latest React native version (0.60).
  • Built new features and UI screens based on Figma design.
  • Implemented scheduled push notifications using FCM.
  • Developed an offline first methodology and backup/restore process for media content.
  • Created REST APIs using Python/Django and PostgreSQL.
  • Deployed and maintained the back end to AWS Elastic Beanstalk.
Technologies: Cypress, SCSS, Microservices, Git, Jest, Express.js, Scrum, Agile, Redux-Saga, Node.js, Enzyme, iOS, Figma, Amazon S3 (AWS S3), Cloud Firestore, Redux, Expo, Firebase, React, React Native
2018 - 2019

Web and Mobile Developer

Spend, Inc.
  • Built a web portal for blockchain crowdfunding and airdrop using WordPress and Angular.
  • Developed REST APIs using Node.js, Express, and MongoDB.
  • Developed dynamic mobile UI screens based on the REST API.
Technologies: Sketch, Git, AWS Lambda, Amazon Web Services (AWS), Amazon S3 (AWS S3), Firebase, Amazon EC2, Android, iOS, Agile, Zeplin, Node.js, JavaScript, Swift, WordPress, Angular
2017 - 2018

Mobile Developer

  • Developed React Native-based mobile apps based on blockchain technology.
  • Analyzed the high-level requirements and converted them into system functions.
  • Implemented a secure chatting function using a signal protocol.
  • Practiced Agile development methodologies and worked with a scrum team.
Technologies: SQLite, Microservices, Git, Test-driven Development (TDD), Jest, TypeScript, PostgreSQL, Scrum, Agile, Amazon S3 (AWS S3), Python, GraphQL, Enzyme, Realm, React Navigation, Redux-Saga, Android, iOS, Java, Web3.js, React, JavaScript, React Native
2016 - 2018

Full-stack Developer

Populous, Inc.
  • Built the financial platform from scratch using Meteor, React, and Node.js.
  • Created REST APIs and Meteor methods for socket communication.
  • Implemented interface with the Ethereum network using Web3.js and Node.js.
  • Converted a UI/UX design into interactive web pages using components from reactstrap and antd (Ant Design).
Technologies: Styled-components, Antd, HTML, SCSS, Git, Redux, Express.js, Amazon Web Services (AWS), Agile, CSS, Amazon EC2, PM2, mLab, Adobe Experience Design (XD), Adobe, Web3.js, Ethereum, MongoDB, Node.js, Meteor, ECMAScript (ES6), React, JavaScript
2014 - 2017

Senior Software Engineer

Avenue Code
  • Analyzed business requirements and created technical specifications.
  • Developed automation scripts using Python and Node.js.
  • Created and deployed web pages with HTML, JSP, JavaScript, and CSS.
Technologies: HTML, Git, Test-driven Development (TDD), Karma, Jest, AWS Lambda, Django, MySQL, CSS, PHP, Ionic, Angular, Ruby on Rails (RoR), MongoDB, C#, Node.js, Python


Sivo - The Future of Finance
Debt as a service provider. Sivo allows customers to access debt funding through their API and also allows users to lend money to their customers at scale.
A React-based website built using TypeScript + GraphQL.
I have worked as a front-end developer and played a key role in building the backbone of the project.
Worked with an agile team that consists of distributed members and had a great relationship with product people too.

Playground App
A social app where users can find all the virtual events in NYC.

I was handed the legacy mobile app code and migrated it to the latest version of React Native and Expo. I then built the required back-end APIs using the Django REST Framework and created a web dashboard for admins and curators to manage virtual events. I worked as the only developer in the project for around eight months and helped the client reach out to several curators that would improve the platform as a whole.


A music-sharing platform that allows independent artists to launch their music, connect with listeners, and be able to live off their art.

I contributed to the web and mobile apps of the project by converting Sketch designs into interactive screens.

Technologies: React, React Native, Redux, Styled Components


Populous is a platform that allows invoice sellers to receive short-term loans from investors, utilizing their invoices as collateral.

For this project, I created a single-page application using Meteor, React, Node.js, and MongoDB. I also deployed the app to AWS EC2 using PM2 and created the UI pages and components utilizing Reactstrap and Ant Design.

Technologies: Meteor, React, Node.js, MongoDB, AWS EC2, PM2, Reactstrap, Ant Design


Built iOS/Android apps using React Native and utilizing the Realm database. I also created several modules to manage the wallets, chat rooms, and offline mode. I implemented the secure chatting function using Signal SDK and encrypted/decrypted all the messages using the algorithm provided.

Technologies: React-native, Socket.IO, TypeScript, Flow, Jest, Enzyme, Realm, Signal SDK

Trend Analytics

Worked on an Angular dashboard to display data coming from the back-end API. I also integrated various charts using D3.js and Highcharts and optimized the entire system, as it was dealing with millions of data every second.

Toptal React Accelerator

The Toptal React Accelerator is an exclusive learning program that educates JavaScript developers in React, NextJS, Redux, and GraphQL. This is a 2-month program that consists of rigorous learning exercises and hands-on activities along with a stringent evaluation process, comprehensive learning assessments, and an Invoice Management System. Within this invoicing application, users are able to track invoices, clients, and company information.



ECMAScript (ES6), JavaScript, PHP, SQL, HTML, CSS, GraphQL, TypeScript, SCSS, Python


AngularJS, React Native, Angular, Express.js, Redux, Jest, Jasmine, Django, Flask, Next.js, Tailwind CSS, Cypress, MUI (Material UI), Ruby on Rails (RoR), Electron, Relay


D3.js, Vuex, Node.js, Antd, Vue, React, Socket.IO, Web3.js


Figma, Expo, Zeplin, Karma, Git, Xcode, Jira, Slack


Agile, Scrum, Test-driven Development (TDD), Microservices, Unit Testing


Amazon Web Services (AWS), Amazon EC2, AWS Lambda, iOS, Android, Firebase, Web, WordPress, Visual Studio Code (VS Code), Ethereum, Docker


Cloud Firestore, MongoDB, MySQL, PostgreSQL, Amazon S3 (AWS S3), SQLite


Apollo, Gatsby, Enzyme, Styled-components, Full-stack Development, Front-end, User Interface (UI), Card Payments


2010 - 2012

Master's Degree in Applied Science

Beijing University of Science and Technology - Beijing, China

2006 - 2010

Bachelor's Degree in Applied Science

Beijing University of Science and Technology - Beijing, China



Toptal React Accelerator Graduate

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