Youngjae Ji
Technical Co-founder CTO at Limelight
Los Angeles, California, United States
Summary
👤
Senior🎓
Top SchoolYoungjae Ji is a technical co-founder and CTO based in Los Angeles with nearly two decades of full-stack engineering experience and 11 years in leadership and product roles. He designs and ships end-to-end web, mobile, and kiosk products, excelling at translating business requirements into scalable Node.js backends and polished front-end experiences using Figma-driven UX. His career spans startups and scale-ups including Uber and SteelHouse, and he’s built infrastructure for safety tooling, marketing integrations, and high-throughput e-commerce systems. An entrepreneur at heart, he’s repeatedly served as a founding engineer or co-founder, most recently building a first-of-its-kind B2B creator ad platform. He contributes to open-source front-end projects—improving UI, routing, and tests on widely used starter kits—demonstrating a pragmatic focus on usability and testability. Colleagues rely on his judgment to balance runtime, maintainability, and delivery speed when shaping production systems.
11 years of coding experience
13 years of employment as a software developer
Bachelor of Science (B.S.), Information Technology and Electric Engineering, Bachelor of Science (B.S.), Information Technology and Electric Engineering at Handong Global University
English, Korean
Github Skills (16)
typescript10
javascript10
typescripts10
react10
typescript-types10
jestjs9
jes9
jtest9
react-router-dom9
apollo8
graphql8
webpack8
wpgraphql8
webpacker8
wordpress-graphql8
Programming languages (18)
Github contributions (5)
sysgears/apollo-universal-starter-kit
Apr 2017 - Jan 2019
Apollo Universal Starter Kit is a SEO-friendly, fully-configured, modular starter application that helps developers to streamline web, server, and mobile development with cutting-edge technologies and ultimate code reuse.
Role in this project:
Front-end Developer
Front-end DeveloperContributions:7 commits, 10 PRs, 41 comments in 1 year 8 months
Contributions summary:Youngjae primarily contributed to the front-end components and testing infrastructure of the application. They addressed a `validateDOMNesting` warning, refactored the `App.jsx` file as a route and updated route configurations. The user also fixed unit tests related to the application, and removed unnecessary elements in test helpers and routes, demonstrating a focus on UI and testing.
streamlinengrxreuseweexultimate
zirho/portfolio
Jun 2016 - Aug 2021
My portfolio website with reactjs
Contributions:67 pushes, 4 branches, 21 issues in 5 years 2 months
reactjsjavascriptreact
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