Full-stack Software Engineer

Raffael Choi.

I build software from the first idea to the system people actually use. Game clients, real-time backends, native apps and local AI.

Explore my workAbout & experience

Open to new roles

Frostify Android player mockup
Real-time systems. Native experiences.Frostcord / Frostify

Selected engineering work

Systems, built end to end.

Different kinds of software. The same responsibility for how all the pieces work together.

The current Frostphone website showing the local AI voice assistant and an illustrative conversation
Live project website Frostphone / 2026
Local AI / Voice systemsWorking

Frostphone

An entire voice pipeline on the operator’s own hardware. From the SIP call to the spoken answer.

Python · LiveKit · Whisper · Ollama

Client login mockup Original client assets / source-based layout
Game engineering / C++In development

Eternal Crossing

An MMO client built in Unreal Engine 5, down to the binary protocol and the world the server reads.

Unreal Engine 5 · C++ · Binary protocols

Desktop application mockup From Frostforge / illustrative community
Real-time / CommunicationIn production

Frostcord

Self-hosted communication, native clients and the infrastructure that provisions a running instance.

TypeScript · React · WebRTC · Node.js

FrostifyPreview
Choose player preview
Illustrative cover: a rain-soaked street at night
Illustrative lyrics

Neon on the water

Footsteps in the rain

We leave the city glowing

And take the long way home

In the app: lyrics from LRCLIB, when available.
Midnight DriveAurora Skies
Cover or lyrics? Try the tabs above.Illustrative app preview. Sample tracks, no audio playback.
FrostifyIllustrative preview
Choose app view

Your collection

Liked songsYour saved tracks
Late Night DrivePlaylist
Focus FlowPlaylist
Illustrative sample content. No connection to music services.
Android player & library Interactive mockups / sample content
Native / AndroidShipped

Frostify

Five music sources in one Android player, with a local library and a Rust layer between the app and the network.

Rust · Tauri · Vue · Kotlin

Also on the workbench / WebSocket game

Kritzl

A multiplayer drawing game with three game modes, live guessing and a shared canvas.

Read the case study
Multiplayer drawing game mockup From Frostforge / illustrative round
2019 - 2023Turtle WoWFour years owning every raid, dungeon and boss encounter on the largest Classic+ server in the world2021 - 2026Nexto BridgeA reinforcement learning policy driving a live Rocket League client at frame rate
13 projects, each with a closer look.View all work

The person behind it

Portrait of Raffael Choi
Raffael ChoiVienna, Austria

The connections are the interesting part.

I’m drawn to the parts where systems meet: a game engine and its server, a phone line and a language model, a web app and the device it runs on. I design, build and operate the layers in between.

From idea to operationArchitecture, implementation, native integration and deployment. I stay with the system after it ships.

Across different worldsC++, Rust, TypeScript and Python. The tools follow the problem.

Background & experience

What’s next

Let’s talk engineering.

I’m open to software engineering roles, based in Vienna and working with teams across Europe and the US. Tell me about the team and the problem you’re working on.

office@raffaelchoi.com
One-page resume ↗LinkedIn ↗