About Me
Self-taught System Engineer & Lifelong Learner
Ha-Rin Seong Dewey-Choi
Self-taught System Engineer
I'm a self-taught system engineer and learner currently studying at Cypress College. Passionate about building, breaking things apart, and understanding how everything works from the ground up. I believe in hands-on learning and real-world problem solving.
What I Know
💻 Systems & Infrastructure
- System administration
- Malware & virus removal
- Software installation & configuration
- Network troubleshooting
🔧 Hardware & Building
- DIY PC building & assembly
- Computer hardware knowledge
- Component selection & optimization
- Troubleshooting hardware issues
⚡ DIY & Hands-On
- Electrical work
- Plumbing & home repairs
- Apartment fixes & upgrades
- Creative problem solving
🚁 Tech Interests
- Drone technology
- Computer hardware exploration
- Tech tinkering & experiments
- Learning new tools & tech
🌐 Web & Development
- Rust programming
- C programming
- Web development
- Emulator development
- Database design (SQLite)
🔐 Networking & Infrastructure
- pfSense router setup
- Home network design
- LAN configuration
- Network troubleshooting
📚 Philosophy
- Self-taught learning
- Hands-on experience
- Real-world applications
- Continuous growth mindset
Experience
🦷 Dental Lab Technician (10 years)
Specialized in CAD/CAM implants, bars, crowns, and bridges. Developed precision skills, attention to detail, and understanding of complex manufacturing workflows. High-pressure environment with 12-24 hour shifts shaped my work ethic and problem-solving abilities.
💻 Full-time Tech Builder
Transitioned from dental lab to pursuing software engineering, coding, and building projects. Currently studying at Cypress College while building real-world applications and exploring system-level programming.
Education & Learning
📚 Cypress College
Currently enrolled as a student, pursuing formal education in computer science and software development
🎓 Self-Taught
Primarily self-taught through hands-on experience, online resources, and learning by doing. I believe the best learning comes from building real things.
🤝 Community & Impact
Involved with UGF (Unity Golf Foundation), working on initiatives that make a positive impact. Always looking for ways to improve efficiency and find better solutions.
My Philosophy
🏗️ Build & Learn
Real knowledge comes from hands-on experience. I learn by building, breaking things, and understanding how they work from the ground up.
💡 Efficiency & Innovation
Always thinking about better ways to do things. Open-minded approach to finding more efficient solutions and creative improvements.
🤝 Community Impact
Committed to making a positive difference. Whether through UGF initiatives or helping others learn, I believe in giving back to the community.
Notable Projects & Work
🎮 Pokémon Red Deep RL System
End-to-end AI training pipeline for Pokémon Red. Custom Game Boy emulator (~3,200 FPS) + Stable Baselines 3 PPO. Trains 64 parallel agents via multiprocess shared-memory IPC. Agents autonomously explore maps, earn gym badges, and progress through the game. CUDA-accelerated inference with reward shaping for game progression tracking.
🎮 Game Boy Emulator (rlgb)
C-based from-scratch Game Boy (DMG) emulator with Python bindings. ~3,200 fps performance, cycle-accurate SM83 CPU, scanline-accurate PPU, deterministic save-states, full MBC1/3/5 cartridge support. Runs Pokémon Red end-to-end.
🚀 RL Training Bridge (rlgb-vec)
Python/C vectorized environment for Stable Baselines 3. Multi-process worker pool, shared-memory IPC, GPU inference batching. Reward shaping for badges, exploration, and levels. Docker support with CUDA 12.1.
🎮 Minecraft Skyblock Server (mc-rust)
Rust-based Minecraft server built on Valence framework. Skyblock gameplay on void world with island, multiplayer support, block breaking/placing, survival mode, chat. Port 25565, Minecraft 1.20.1 compatible.
⚡ Rust Systems Programming
Multiple Rust projects: game servers, emulation, infrastructure. Low-level system programming, performance optimization, networking, real-time processing.
🔧 CUDA & GPU Computing
GPU-accelerated projects leveraging CUDA for parallel computation. Optimization for GTX 1080 and modern compute capabilities.
🏌️ Unity Golf Foundation
Involved with UGF as an almost-nonprofit initiative. Worked on various projects to support community goals and improve operations.
🌐 BuiltNotTaught.com
This website itself! Built with Rust, Axum web framework, SQLite database, and modern web practices. Demonstrates full-stack development with async Tokio runtime and Stripe payment integration.
Stack: Rust, Axum, SQLite, Tera Templates, Stripe API
Why BuiltNotTaught?
BuiltNotTaught represents my philosophy: learn by building, not just reading. Whether it's coding, fixing computers, building PCs, setting up home networks, or working on community projects—real knowledge comes from hands-on experience. This site is where I share that journey and help others learn the same way.