Congwen Ma, Software Developer in Dublin, CA, United States
Congwen Ma

Software Developer in Dublin, CA, United States

Member since November 4, 2017
Congwen is a dedicated web developer who specializes in developing full-stack web applications using practical frameworks. He's passionate about solving problems for others—a good solution to him usually requires a dose of creativity that then requires more effort to adapt and perfect.
Congwen is now available for hire


  • Rally Health
    Angular, Ruby on Rails (RoR), Scala
  • UpCounsel
    MongoDB, Ruby on Rails (RoR)
  • Centro
    PostgreSQL, AngularJS, React, Ruby on Rails (RoR), Ruby



Dublin, CA, United States



Preferred Environment

Linux, MacOS, Vim Text Editor, VS Code

The most amazing...

...thing I've made was a Chrome DevTool extension that renders a visual tree graph of my company's proprietary framework.


  • Principal Software Engineer | Engineering Manager

    2019 - PRESENT
    Rally Health
    • Designed and invented solutions and coding patterns to solve front-end problems.
    • Mentored the team to understand FE technologies and trade-offs in practical scenarios.
    • Proposed and led data schema changes that improved product with minimum effort, eliminating tech debts.
    • Led the engineering effort of developing a new product.
    Technologies: Angular, Ruby on Rails (RoR), Scala
  • Full-stack Software Engineer

    2018 - 2018
    • Built concrete Ruby on Rails APIs that carried out tasks via Node.js microservices.
    • Developed and implemented a strategy for migrating FE code base to React additively.
    • Designed and implemented NoSQL solutions based on an in-house framework.
    Technologies: MongoDB, Ruby on Rails (RoR)
  • Software Engineer

    2014 - 2018
    • Constructed a Chrome developer tool to help developers debug and analyze a proprietary state-management framework.
    • Used jscodeshift (a JavaScript codemod toolkit) to make application-wide code changes to replace deprecated APIs and code syntax.
    • Constructed middleware that allowed React to work with our proprietary model framework.
    • Built and analyzed an ad exchange platform with React/Angular 1 frameworks.
    • Developed friendly Ruby on Rails APIs for our front-end application.
    Technologies: PostgreSQL, AngularJS, React, Ruby on Rails (RoR), Ruby
  • Software Engineer

    2012 - 2014
    • Developed responsive mobile web applications with AngularJS.
    • Mentored experienced developers who were new to JavaScript.
    • Analyzed front-end technological options (CSS frameworks, Protractor, design patterns, and more) and helped the team settle upon our technology foundation.
    • Led the development of Sears eCoupon application with a similar criteria and oversaw its deployment and integration with Sears' subsidiary domains.
    Technologies: Java, jQuery, AngularJS


  • Cartographer

    A Chrome developer's tool that generates a diagram on-the-fly for applications running on Statechart.js, see more at It helps developers visualize the state of the application and captures applications' live states.

    The noticeable outcome of this project includes:
    • New developers can understand the purpose of our framework much quicker.
    • Enabled the back-end developers to become better at writing front-end state-related code and understanding the underlying framework.
    • Reduced the amount of unit testing that needed to be done for state management.
    • Provided a common ground for discussions and planning around state management; this tool became the main visual representation used to analyze options.

  • Xiang Qi

    A complete JavaScript attempt of the popular Song dynasty board game. The pieces and the graphics were rendered using SVG on the React framework. The AI moves were determined by examining and evaluating part or all of the subsequent options and finding the maximum of gains around these options.

  • eCoupons

    A simplified version of Shop Your Way mobile coupons application. It has built-in Angular code and is styled mainly in the ShopYour Way proprietary version of Bootstrap.

    It provides a list of coupons that have certain categories and availability tagged with them. The user may filter coupons by specifying the criteria (e.g., category). The application was eventually restyled to fit into Sears/Kmart mobile web application. I led a small team of two developers to focus on the user experience distinctions between the tablet and phone.

    My main roles in this application include:
    • Performant loading and filtering process with the resource APIs which present coupons efficiently to the user.
    • Optimized the JavaScript code to achieve a maximum speed between when the data is received and when the coupons are displayed.
    • Automated integration with Sears, Kmart, and Shop Your Way.
    • Enhanced the end product which included resizing and animating the layout transition from portrait vs landscape view in a pixel-perfect manner.
    • Oversaw its delivery and QA feedback.

    Official URL:

    Official Sears URL (rethemed and restyled for the tablet):

  • Song Cloak

    A video player that uses a YouTube third-party JavaScript library and Google OAuth 2. I developed it in React.js and Rails and this application loads your favorite playlist from your YouTube account and plays the content by embedding the video's content in a video tag.

  • Memory Game

    A simple game that looks for two identical tiles at a time. The UI was built with React and MobX was used for state management.

  • Chess in Elm

    A simple chess game built in Elm. Some advanced moves such as castling and promotions were left out. This was made mainly to visualize and understand Elm's behavior in handling DOM manipulation and large computations.

  • Centro Media Manager

    Centro Media Manager is a cloud-based web application platform designed to help create and execute data-driven digital media campaigns.

    I handled the development and communication of its inventory management Rails API. I also built the front-end application as well as maintaining and designing the APIs that connected our in-house JavaScript frameworks for communication with third-party APIs such as React.

  • Sears White Label Cart and Checkout

    I developed a white-label cart and checkout feature (including many of its payments systems) that was part of a customizable mobile-based online shopping application that we built at Sears; it mainly focused on cross-platform compatibility and dynamic themes by using Angular 1 and Foundation CSS.

    You'll need to simulate a mobile device in order to access the app without being redirected.


  • Languages

    JavaScript, Ruby, Elm, CSS, Bash Script, TypeScript, Java, Java 6, Scala
  • Frameworks

    .NET, AngularJS, Ruby on Rails (RoR), Hyperapp, Electron, React Native, Bootstrap, Redux, Protractor, Express.js, Angular
  • Libraries/APIs

    Statechart.js, React, Node.js, TensorFlow, D3.js, Vue.js, jQuery
  • Tools

    Webpack, Jscodeshift, Rollup, Vim Text Editor, VS Code
  • Paradigms

    Behavior-driven Development (BDD), JavaScript Design Patterns, Functional Programming, Agile
  • Platforms

    MacOS, Visual Studio Code, Linux
  • Other

    Mobile Web, Front-end Development, Elm Architecture
  • Storage

    PostgreSQL, MySQL, MongoDB


  • Bachelor of Science degree in Infromation Systems
    2008 - 2012
    SUNY Stony Brook University - Stony Brook, NY, USA

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