Technical Director · MMO Server Architect — 20 years building game servers (since 2007), at NCSOFT since 2016.
I build MMO server frameworks from scratch — networking, lock-free concurrency, navigation, server-side physics and virtual-actor distributed systems — and I optimize across the whole stack: server, client and database. I prefer leading technology hands-on to leading it through management.
📄 Resume (English) · 이력서 (한국어 · 전문) · 3D interactive 💼 LinkedIn · ✉️ jungrok5@gmail.com
| 13M packets/sec | 1,000-player single-view combat, scaled to 2,000 vs 2,000 · traffic −36% — NCDP 2019 Grand Prize |
| 50M props | full-tick in one space with 2,000 concurrent builders (UE5) |
| 20,967 → 503 | draw calls, with FPS 16.5 → 47.4 (instancing + physics chunking) |
| 240K req/sec | gRPC load-test ceiling · 50K TPS on EntityFramework |
| 1,000+ cursors | synchronized in a single browser space, conflict-free |
| 2,000 → 8,000 | stable concurrent users, 3-month optimization assignment |
Experiments in how far each domain can be pushed with AI and models as tools.
| Project | What it is | Notable |
|---|---|---|
| Hellfarm 🔒 | Hack-and-slash action game (Godot · C#) | 128M entities simulated concurrently; dense-horde O(n²) cut from 2,500 ms to 38 ms per frame |
| ZeroLlama 🔒 | Agentic coding client for local models (TypeScript · llama.cpp) | Runs a 35B-class model on 8 GB VRAM by offloading MoE experts to CPU RAM |
| ondevice-imagen | On-device image generation (Kotlin · ONNX Runtime) | Stable Diffusion inference pipeline implemented natively for Android |
| one-scroll-bible | The Bible as one scroll, 200+ languages | Live at one-scroll-bible.com |
| thesauros | Equity buy-timing analysis and alerting | Production: collection → analysis → backtest → alerts |
C++ 11–20 C# TypeScript Python Lua GDScript Kotlin
Orleans gRPC/TCP IOCP ASP.NET Node.js sharding
MSSQL Redis/Garnet MongoDB EntityFramework
Unreal Engine 3/4/5 Unity3D Godot Recast/Detour voxel navmesh
MCP (own implementation) llama.cpp ONNX Runtime