Hyoseo Lee
01 Index 02 Writing 03 Current page Work 04 Notes 05 Games 06 Author

Proposition.

Philosophy of Code

Software is not just logic; it's a medium for expressing care. I build tools that aim for the quiet intersection of utility and beauty.

Projects
13
Archived
2
In flight
HN Scroller
Latest
present
Hacker News 412 pts

someone found a way to make ChatGPT stop producing horrible event posters

next
Hacker News 268 pts

a font format from the eighties turned out to have a hole big enough to run code through

next
Hacker News 531 pts

Postgres got a change that stops huge tables locking up during an upgrade

next
detail
quote verified against source

Rewriting the visibility map lets ALTER TABLE run without an exclusive lock, so a 400 GB table upgrades while it keeps serving reads.

Discussion Glossary Article
Now Building

HN Scroller

Python stdlibGemini APIvanilla JSCSS scroll-snapGitHub ActionsCloudflare Pages

Hacker News as a vertical swipe feed — enough to know what happened in tech, in about two minutes. Swipe up for the next story as one plain sentence, swipe right for the figures behind it; both axes are plain CSS scroll-snap, no framework. A nightly GitHub Action has Gemini write the cards into one JSON file a day, and the commit is the deploy — no server, no build step, no dependencies.

Source Live 2026.09 - present
The Build Log —

2026

Drop your CV here
Hyoseo_Lee_CV.pdf
waterlooworks · co-op postings
Software Developer Intern
Some Co.
scoring
9 apply
Data Analyst — Coop
Other Inc.
scoring
6 Maybe
Marketing Assistant
Brand Co.
scoring
3 Skip

WW Extension

Archived (2026) 2026.05 - 2026.07
Chrome MV3 FastAPI Supabase React Stripe Gemini API

An AI job scorer for WaterlooWorks, UWaterloo's co-op board. Gemini rated each posting 1–20 against your profile and the scores landed as badges in the job table, so you could triage hundreds without opening one. Passed Chrome Web Store review, ran in production for two months, scored 1,749 real postings — then wound down with the co-op term it was built for. The backend has since been shut down, so the extension no longer runs; the source and the walkthrough are what's left of it.

news
  • 2m Fed signals rate cut next quarter
  • 8m Tech stocks rally on AI earnings
  • 1h Oil prices steady as supply rises
₿ BTC/USD +1.2%
$67,432.18
$67,478.94
$67,521.05
S&P 500 +0.8%
5,463.21

Macro-dashboard

2026.04 - 2026.05
React 19 TanStack Query react-grid-layout FastAPI SQLAlchemy Alembic APScheduler PostgreSQL yfinance feedparser Gemini AI Docker Compose

A highly customizable finance dashboard that helps users build the habit of 'looking around' — showing asset prices and news on a single screen. Async SQLAlchemy over PostgreSQL with Alembic migrations, APScheduler jobs pulling quotes and feedparser news on a timer, and a React 19 front end where every widget drags into the layout you want. Ships as a production docker-compose.

Drop teaching materials
vocab.txt
grammar.md
generated
quiz.pdf
dialogue.md
flashcards.csv

English material provider for Korean language Project (EMPKL)

2026.03 - 2026.03
fastapi gemini api vite tailwind css postgresql

A web application that provides English learning materials for Korean speakers. Utilizes Gemini API for content generation and features a modern frontend built with React and Tailwind CSS.

hyoseo.dev/ hyoseo.dev/projects hyoseo.dev/blog
Hyoseo Lee
building things, writing about them
latest: ww-extension
Projects
ww-extension 2026.05
macro-dashboard 2026.04
EMPKL 2026.03
Blog
2026.05 · TIL
Astro v6 scoped CSS gotchas
2026.04 · dev-log
Refactoring the projects page
2026.03 · brain dump
On side projects

Personal Website and Blog Renewal

2026.03 - 2026.03
Astro TypeScript Tailwind CSS cloudflare pages

Redesigned and rebuilt my personal website and Blog with a modern look and improved performance.

2024

term
Recursion
definition
A function that calls itself
term
Big-O
definition
Notation for algorithm complexity
term
DFS
definition
Depth-first traversal of a tree

Dchup (Study Card Webapp)

Archived (2024) 2024.03 - 2024.07
React Python-fastapi AWS

Built a full-stack flashcard architecture aimed at providing a Quizlet-like experience. A deep dive into backend systems and data persistence.

cost function
training
cv
predicted · alberta
A
B
C
D
E
n = 22,000

CxC Hackathon: Wildfire Analysis

2024.02 - 2024.03
Python Pandas Matplotlib AI

Analyzed 22,000 wildfire records in Alberta. Built an AI model to predict wildfire sizes and understand their impact on indigenous civilizations. Won the MEF Award.

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Solitaire (React)

2023.10 - 2024.01
React

A complete reconstruction of the SHENZHEN I/O solitaire card game in React. The project where I truly mastered React's state management.

2023

Orbt!

2022.02 - 2023.05
HTML CSS JavaScript

A minimalist mini-game built as a Chrome Extension. Focused on smooth animations and simple, addictive mechanics.

solving RUR'U'FR'F'R

Rubik's Cube Helper

2022.07 - 2023.05
Python Pygame

IB Computer Science IA project. A solver that visualizes the solution process for a Rubik's cube with a custom UI.

z³ − 1 = 0
Newton fractal for z³ - 1

Newton Fractal Generator

high school - 2023.05
C++

IB Extended Essay project. Researched complex numbers and Newton's method to generate precise fractal images at specific resolutions.

F = G m₁m₂ / r²

Gravitational Motion Simulator

high school - 2023.05
C++ SFML

A physics simulator based on the laws of gravitation. Calculates field strength and executes based on classical mechanics.

Infection Simulation

high school - 2023.05
Python Pygame

MYP Personal Project. A simulator that visualizes disease spread based on simple contact rules.