$ whoami

Taejin Yi

Developer × Finance

ETF LP at a Securities Firm · 15 Years in Dev

Writing code in Yeouido. Building products at the intersection of finance and technology.

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## About

For 15 years, I've been building products across trading systems, mobile apps, and everything in between — bridging development and finance.

Currently working as an ETF Liquidity Provider at a securities firm, where I design and develop ultra-low-latency market-making systems operating at nanosecond precision.

Outside of work, I explore the edges of technology through side projects spanning blockchain fintech, AI apps, and educational services.

## Projects

VISION

In Development

Vanguard and Intelligent Self-neutralizing Intermarket Order Nexus

Ultra-low-latency OMS for ETF Liquidity Providers. Rust-based HFT engine.

Rust Tauri React gRPC

Coinluck

Building

P2P Blockchain Fintech Platform

P2P fintech platform abstracting multiple blockchain providers through a unified interface. Provides wallet management, P2P transfers, credit unions (SOCU), and payment services.

Django gRPC Swift Kotlin Solidity

Kimchi Hunter

Live

CEX-DEX Kimchi Premium Auto-Trading

Rust-based trading platform that tracks the kimchi premium between Bithumb and Binance in real-time, capturing spreads through automated grid trading.

Rust Axum React PostgreSQL WebSocket

App Store Review

Traditional Fortune-Telling AI Compatibility Platform

Social platform combining traditional Korean fortune-telling (Saju) with AI for relationship compatibility analysis. Features contact-based friend management, AI consultation chat, face reading, and fortune tracking. Currently in Android open beta.

Django Next.js Swift Kotlin Claude API

끈톡

Building

Mood-Based AI Social Matching Platform

Social platform where AI recommends people matching your current mood and connects you through AI-mediated chat. Combines MBTI and AI vision first-impression analysis for optimal matching.

Django Next.js Swift Kotlin Claude API

Vocaid

App Store Review

OCR-Powered Vocabulary Learning App

Vocabulary app that captures words from any screen via OCR and provides scientifically-backed spaced repetition learning with the FSRS algorithm. Capture words from Netflix, YouTube, and anywhere else.

Swift Kotlin Supabase Vision OCR

APTWallet

Building

Apartment Mortgage P2P Investment Platform

Two-sided marketplace for apartment mortgage P2P investments. Connects borrowers and investors through Google Maps interface powered by official Korean real estate transaction data.

Django Next.js Google Maps PostgreSQL

닥톡

Building

Your body's recorder, your doctor's translator

Health platform that closes the doctor-patient information gap through AI symptom triage and automatic summarization of clinical visit recordings. Offers pre-visit symptom consultation, post-visit comprehension support, and a personal health timeline.

Swift Django Claude API SenseVoice

## Tech Stack

Languages

Rust Python Swift Kotlin TypeScript Solidity C#

Frameworks

Django Next.js React Tauri SwiftUI Jetpack Compose Astro

Infrastructure

PostgreSQL Redis gRPC Supabase Cloudflare GitHub Actions Nginx

Finance

FEP Protocol HFT ETF LP Market Making OMS

## Contact

Open to project collaborations and tech conversations.