Production systems and shipped products — mostly solo, AI-pair-programmed. Each page carries a dated build log: what broke, what I changed, and what it still can't do.
A real-time 1v1 PvP game from the Korean schoolyard 기싸움 hand game — read the opponent, charge ki, strike on the right beat. Python (FastAPI) and a second Go runtime share one Redis-backed game state; Next.js 16 PWA, room-based PvP, 6 character ultimates, AI-generated sprites.
Python 3.11 · FastAPI · Go 1.23 · Next.js 16 · React 19 · PostgreSQL · asyncpg · Redis · Caddy · Tailwind v4
A private, installable PWA for keeping the encouragement of the people who love you — voice, photo, a kind word, a short clip — and surfacing it on the hard days. One codebase: zero-account local to full production infra by env var alone.
Next.js 16 · React 19 · TypeScript · PostgreSQL · Drizzle · PWA · Web Push · S3 / R2 · Terraform · Tailwind v4
The cockpit around your own Claude Code / Codex — a native AI work operating system that gates risky agent actions behind your approval, re-runs the commands behind a 'done' claim to catch false ones, and captures decisions into a searchable project-memory graph. Tauri + Rust, macOS.
Tauri 2 · Rust · React 19 · TypeScript · xterm.js · portable-pty · tmux
Turn any YouTube video into spaced-repetition English shadowing, plus daily drills for the grammar patterns, collocations, and prepositions that never come automatically. Java/Spring + Next.js, built solo.
Java 21 · Spring Boot 3.3 · PostgreSQL 16 · Next.js 16 · TypeScript · Gemini / Claude · AWS ECS
A self-built interview-prep platform. The public Lab reproduces production database failures — N+1, connection-pool exhaustion, deadlock — on demand against a real Spring Boot + JPA + PostgreSQL/HikariCP backend, and visualizes data-structure internals over a deterministic 'typed state → SVG view → instant confirmation' engine. Next.js 15 + a containerized Java runner.
Next.js 15 · React 19 · TypeScript · Tailwind · MDX · Spring Boot
A macOS desktop tool that translates abstract AI instructions ('open VS Code, edit X') into concrete pointer actions on your actual screen — via ScreenCaptureKit + Accessibility APIs + a vision LLM.
Swift 6.3 · SwiftUI + AppKit · ScreenCaptureKit · AXUIElement · Vision OCR · Anthropic Claude Sonnet 4.6 (vision)
A real-time English assistant for Koreans on working-holiday visas, targeting Meta Ray-Ban Display. iPhone app + Bun backend + Gemini vision; building against a Mock Device Kit while Display SDK access is pending.
Swift / iOS · Bun · Node.js · Gemini 2.5 Flash (vision) · BLE · Mock Device Kit
This site. Bilingual blog + private admin dashboard for drafts and distribution.
Next.js 15 · TypeScript · Tailwind · MDX · Vercel