Sunhyoup Lee

Platform Engineer

I make software, and I sometimes rewrite code that already works just because it reads badly.

Experience

  1. 2026 – now

    Toss

    Frontend Platform Engineer, Tech Lead

  2. 2025 – 20261 yr 1 mo

    Marpple Corporation

    Backend Platform Engineer, Lead

  3. 2018 – 20246 yrs 6 mos

    CoBALT, Inc.

    CTO

  4. 2017 – 20187 mos

    Jininsa Company

    Full-Stack Engineer

  5. 2016 – 20171 yr 5 mos

    Poing

    Full-Stack Engineer

  6. 2014 – 20162 yrs 4 mos

    Parking Square / TheVentures Lab

    Full-Stack Engineer

Talks

  1. 2025.11

    Using AI Agents to Solve Problems DEVCON 2025

  2. 2025.08

    Building a Grid-Based Editor and Builder FEConf 2025

  3. 2025.06

    Railway-Oriented Programming and Spring Spring Camp 2025

  4. 2024.10

    The Art of Software Destruction DEVCON 2024

  5. 2024.06

    Using Kotlin Script KotlinConf Global 2024 in South Korea

  6. 2023.08

    Abstract and Structural Thinking for Software Design INFCON 2023

  7. 2021.08

    Building a Design System in a Startup NAVER FE devtalk 20

  8. 2018.12

    Deep Dive into Vue.js Vuetiful Korea 6th with LINE

  9. 2018.04

    A Guide to Vue.js NAVER FE devtalk 11

  10. 2017.09

    Providing Unique UI/UX with Metal Let'Swift 17

  11. 2017.08

    Reactive Programming with Vue.js Vuetiful Korea 2nd

  12. 2017.04

    Reactive Programming with Swift Swift Korea Meetup

  13. 2014.04

    Secrets of C++ Code Quality Management NHN NEXT

Open Source

  1. ★ 3.2k

    qart.js github.com/kciter/qart.js

  2. ★ 1.6k

    Floaty github.com/kciter/Floaty

  3. ★ 1k

    GlitchLabel github.com/kciter/GlitchLabel

  4. ★ 252

    ASCII 3D Renderer github.com/kciter/ascii-3d-renderer.js

  5. ★ 48

    co-design github.com/cobaltinc/co-design

  6. ★ 34

    slidef github.com/kciter/slidef

  7. ★ 18

    NNGameFramework github.com/kciter/NNGameFramework

Publications

  1. 2026

    AI Agent Design for Problem Solving

  2. 2024

    Coding Test Success: JavaScript Edition

  3. 2024

    Micro State Management with React Hooks Korean translation

  4. 2017

    Vue.js Essentials

Tech Stack

  1. Language

    Kotlin, TypeScript, Python

  2. Backend

    Spring, Nest.js

  3. Data & Messaging

    RabbitMQ, Kafka, Redis, MySQL, PostgreSQL, MongoDB

  4. Frontend

    React, Next.js

  5. Infrastructure

    AWS, Docker, Prometheus, Grafana, Terraform, Pulumi, ArgoCD, Kubernetes, GitHub Actions

Education

  1. 2023

    Bachelor's Degree Examination for Self-Education Computer Science and Engineering, degree conferred

  2. 2013 – 2018

    NHN NEXT Game Server, Game Client, completed

  3. 2010 – 2013

    Sunrin Internet High School Web Operations, graduated