Leo Liu, Software Developer in New York City, NY, United States
Leo Liu

Software Developer in New York City, NY, United States

Member since July 29, 2019
Leo is a full-stack developer, technology enthusiast, and University of Waterloo CS fellow. With a full-hearted pursuit in the web development field, Leo has led and engineered products in both React and AngularJS; built back ends in Ruby on Rails and Django; architected full-stack applications with REST or GraphQL; and leveraged databases, such as MySQL, Postgres DB, and Firebase, all with his peculiarly strict standards for Git commits.
Leo is now available for hire


  • Cedar Cares
    Django, React, TypeScript, Apollo
  • Mitre Media
    Apollo, GraphQL, Kubernetes, Docker, MySQL, React, Ruby on Rails (RoR), Ruby
  • Uberflip
    JavaScript, CSS, HTML, PHP



New York City, NY, United States



Preferred Environment

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

The most amazing...

...project I have accomplished is migrating a 10-year-old codebase that faces millions of users.


  • Senior Software Engineer

    2021 - PRESENT
    Cedar Cares
    • Designed and deployed a pillar on-call procedure with an escalation process, risk assessment, and rotation that serves as the backbone of upholding high product quality and driving patient satisfaction levels past 90%.
    • Designed and led the implementation of a large-size product feature that allows millions of patients to submit client personalized registration forms effortlessly, proving value for the Cedar Pre product and improvement.
    • Navigated through difficulties, integrating with external vendors and the largest health system in South Caroline with millions of end users to a successful launch of the Cedar-Pre product, contributing to a contracted annual revenue of millions.
    • Managed and guided a software engineer intern on a client-facing, highly requested product feature to completion, providing an exceptional internship experience and growth opportunity.
    • Wrote extensive documentation and mentored all new engineers into the pillar, achieving increased engineering efficiency and satisfaction.
    Technologies: Django, React, TypeScript, Apollo
  • Full-stack Developer

    2018 - 2021
    Mitre Media
    • Reduced server response time significantly, using different caching strategies, assets management, and database querying optimization in MySQL.
    • Architected and implemented a front-end system for a React application with MUI, styled components, and animation using React Pose.
    • Incorporated React strategies, such as higher-order components, render props, and global state management, using Apollo client caching.
    • Leveraged the proxy pattern in the back-end Ruby on Rails application to retrieve and process financial data through third-party REST APIs.
    • Migrated over 70% of the legacy codebase in PHP and Rails 3 to Rails 5 to a smart (dynamic) components architecture.
    • Proposed and developed a GraphQL endpoint for its advantage of a single data source while developing a GraphQL schema foundation in Rails and a reusable mutation query structure in React with Apollo.
    • Managed assets, using Webpacker in Rails for optimization.
    • Implemented an entire rebranded UI/UX on two major products that average one million monthly page views, using HTML (HAML), CSS (Tailwind.css), and JavaScript (Stimulus and EventQueue system, Webpack compiled) within two to three months.
    Technologies: Apollo, GraphQL, Kubernetes, Docker, MySQL, React, Ruby on Rails (RoR), Ruby
  • Software Developer

    2016 - 2017
    • Administered a reusable in-house web app to process issues and commit data from Redmine and Jira for SR&ED review, using a pure JavaScript solution.
    • Promoted code quality and standards by implementing various custom Git commit hooks.
    • Employed a PHP mass detector and PHP linting tools to maintain code integrity and visibility among the development team.
    • Streamlined developer workflow process by developing custom Jira development dashboards and queries.
    • Performed bi-weekly sprints, story point estimations, retrospectives, and code reviews in an agile manner.
    Technologies: JavaScript, CSS, HTML, PHP
  • Cloud Apps Software Developer

    2016 - 2016
    • Leveraged a UI/UX designer's expertise and excelled in redesigning Autodesk Fusion Life Cycle's main UI.
    • Initiated additional measures for page load time performance and UI improvements.
    • Strived for a detailed inspection of a peer code review and suggestive comments.
    • Skillfully practiced the use of AngularJS and SASS for feature development.
    Technologies: Grunt, AngularJS
  • C/C++ Software Programmer

    2015 - 2015
    Fugawi Softwares
    • Created several in-house utilities, leveraging object-oriented architecture, parallel processing, and command line support.
    • Designed a graphical user interface for utilities, using Qt Creator with an MVC architecture.
    • Delivered projects using GDAL (Geospatial Data Abstraction Library), Boost, and Qt libraries for data processing and manipulation.
    Technologies: Qt Creator, C++, C
  • Software Engineering

    2015 - 2015
    Imagine Communications Corp
    • Created a full record logging feature for all critical user interactions with the company's media software.
    • Identified and conducted fixes to software regarding 32 bits and 64 bits operating system discrepancies.
    • Operated and maintained version control using Mercurial and CVS.
    Technologies: C#


  • Mobile App

    ❖ Established Facebook, email, and phone authentication using the Firebase authentication system.
    ❖ Handled storage and database using the Firebase cloud storage.
    ❖ Composed and designed a rich mobile front-end interface using React-Native for iOS and Android devices.
    ❖ Built reusable components throughout for simplicity and maintainability.
    ❖ Fluent with the Apple credentials set up and Testflight upload configuration using FastLane.
    ❖ Incorporated Crashalytics to monitor potential testing failures.
    ❖ Prepared to scale the application with a back-end REST API and Node.js for the web application.

  • University Club Website

    ❖ Designed and developed an informational website using a minimalistic theme.
    ❖ Ran the back end with Express.js and composed views with EJS (Embedded JavaScript).
    ❖ Hosted the application on an Amazon EC2 instance and routed it with Route 52.
    ❖ Utilized a semantics UI for visuals and a responsive design.
    ❖ Integrated an in-page PDF reader, feedback form submission, and Google API integration for location.


  • Languages

    Ruby, JavaScript, Sass, CSS, GraphQL, HTML5, JavaScript 6, Java, TypeScript, CSS3, HTML, C#, C, PHP, C++, Python 3, Bash
  • Frameworks

    Ruby on Rails (RoR), Tailwind CSS, AngularJS, Bootstrap, Cypress, React Native, Django, Flutter
  • Libraries/APIs

    React, REST APIs, JSON API, Node.js, Google Maps API
  • Tools

    Jira, Git, RSpec, Docker Compose, JSS, Grunt, Qt Creator, Webpack 4, Babel
  • Paradigms

    Agile Software Development, Continuous Integration (CI), Continuous Development (CD), REST, E2E Testing
  • Platforms

    Firebase, Visual Studio Code (VS Code), Web, Netlify, MacOS, Linux, Docker, Kubernetes
  • Other

    Freelancing, Gatsby, Semantic UI, Apollo, Networking, Artificial Intelligence (AI), Machine Learning
  • Storage

    MySQL, MongoDB


  • Bachelor's Degree in Computer Science
    2012 - 2017
    University of Waterloo - Waterloo, Ontario, Canada

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