Jai Ko, Software Developer in Walnut Creek, CA, United States
Jai Ko

Software Developer in Walnut Creek, CA, United States

Member since March 31, 2018
Jai is a skilled front-end developer with expertise in jQuery, Vue, and React, among other front-end technology. He played an instrumental role in the operation of Steps Education, increasing its revenue by 250%+ over the course of three years. At his most recent role at Pilot.com, he created the dashboard, employee time tracker, and the customer portal, which helped employee efficiency, analytics, insights, and communications.
Jai is now available for hire


  • Pilot.com
    Git, PostgreSQL, NPM, Webpack, Vue-router, Vuex, Vue CLI, Vue.js
  • Persona
    Vue-router, Vuex, Vue CLI, Webpack, React Native, Vue.js
  • Steps Education
    MySQL, PHP, jQuery, JavaScript, CSS, HTML



Walnut Creek, CA, United States



Preferred Environment

Visual Studio Code, MacOS, Windows

The most amazing...

...app I've created solves the KenKen puzzle, which is like sudoku, but with math.


  • Front-end Developer

    2019 - 2019
    • Developed and tested pixel-perfect UI based on a provided design.
    • Communicated with stakeholders such as designers and product specialists to improve the existing UI and initiate new projects.
    • Set precedents in coding styles, discussion practice, and other elements of company-wide engineering culture.
    • Communicated with back-end engineers to spec out front-end needs.
    • Recreated the dashboard page that displays thousands of customer statuses with details about their work completion, assignee, and other information.
    • Made asynchronous calls to a REST API via JavaScript Promise to update pages.
    • Optimized the pre-existing codebase by modernizing it with the newest standard of HTML/JavaScript/CSS and adding greater test coverage.
    • Documented progress, accomplishments, and technical specs for added features and debugging.
    • Addressed bugs and comments with short turnarounds.
    Technologies: Git, PostgreSQL, NPM, Webpack, Vue-router, Vuex, Vue CLI, Vue.js
  • Front-end Developer

    2019 - 2019
    • Helped make an engaging and informative web page using Vue and its ecosystem.
    • Built a user and admin dashboard as a single-page application.
    • Connected the front-end and the "wire," a propriety back-end interface created by the back-end team to serve the browser extension, web app, and native app.
    • Worked with the design/UI team to implement beautiful and functional apps expediently.
    • Configured webpack, Vue CLI, and Babel to serve our need.
    Technologies: Vue-router, Vuex, Vue CLI, Webpack, React Native, Vue.js
  • Founder/Full-stack Developer

    2015 - 2017
    Steps Education
    • Created the front end to lazy load various math app plugins using jQuery Ajax functions.
    • Implemented a performance tracking system to measure students' active time, assignment completion, and comprehension using JavaScript.
    • Stored, retrieved, and analyzed various user metrics with PHP and MySQL.
    • Designed UI/UX from the ground up and implemented it using HTML/CSS/JavaScript/jQuery.
    • Planned, designed, and implemented various math apps to help students understand math, which could then be plugged into the platform.
    Technologies: MySQL, PHP, jQuery, JavaScript, CSS, HTML


  • MathTestNinja

    MathTestNinja is created as a demonstration of Jai's capability to make a fully functioning web application from the ground up using modern tech stack, which in this case is Vue, Vuex, Vue Router, Firebase Hosting, and Firebase Authentication.

  • Tweet Streams

    A web app that displays tweets and mentions for select accounts. It asynchronously loads initial and subsequent tweets/mentions, routes Twitter REST API from the back to the front via the cloud, saves and loads user preferences in local storage, and features drag-n-dop layout customization.

    This project involves Vue, Vuex, and Firebase Hosting.

  • KenKen Solver

    An app that can solve KenKen, a puzzle similar to Sudoku, but with arithmetic. It uses a custom-made algorithm to traverse the solution space and find the correct solution.


  • Languages

    JavaScript, HTML, CSS, PHP, PHP 5
  • Libraries/APIs

    Vuex, Vue.js, Vue.js 2, jQuery, React
  • Frameworks

    React Native
  • Tools

    NPM, Vue CLI, Webpack, Git
  • Paradigms

    Object-oriented Programming (OOP), Functional Programming, Test-driven Development (TDD)
  • Platforms

    MacOS, Linux, Windows, Visual Studio Code
  • Storage

    PostgreSQL, MySQL
  • Other



  • Bachelor of Science degree in Mathematics
    2005 - 2011
    University of Washington - Seattle, WA

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