I build language runtimes, developer tools, and game infrastructure—mostly with Kotlin and Rust.
- Electrical Engineering student at the University of Seoul
- Interested in programming languages, runtimes, security, and game tooling
- Based in Seoul, South Korea
- Project Aris — a LuaJIT-powered scripting platform for Minecraft 1.21.4, with generated APIs and Fabric/NeoForge support.
- aris.luagen — a KSP-based generator for fast Kotlin/JVM-to-Lua bindings, API schemas, and documentation.
- Kei — a small, self-hosted build server written in Rust, with GitHub webhooks, Nix development shells, and artifact hosting.
| Upstream | Contribution |
|---|---|
| dotnet/TorchSharp | Contributed a C#-native DataLoader to the .NET bindings for PyTorch. |
| deepjavalibrary/djl | Resolved native-library loading issues on Apple Silicon Macs. |
| gudzpoz/luajava | Added Lua C API methods that were missing from the Java FFI surface. |
| tamarin-prover/tamarin-prover | Fixed parser behavior in the formal security-protocol verification tool. |
| rust-lang/rust | Prepared the rustc_errors crate for internationalization. |
| ScottPlot/ScottPlot | Fixed a scaling issue in the .NET plotting library. |
- Programming languages & runtimes: compilers, JIT-integrated runtimes, code generation, and language interop
- Game development: Minecraft modding, scripting systems, and Godot
- Systems & security: Rust, C/C++, assembly, embedded systems, and vulnerability analysis
- Problem solving: Codeforces Expert (
dayodayo) and solved.ac Diamond 4 (dayo05) - Languages I use most: Kotlin, Rust, C#, Python, C, and C++
- Software Maestro 15th — Youngest: built LCS, a persistent mobile AI agent designed to run without an NPU and powered by LuaJIT.
- Best of the Best 14th — Vulnerability Analysis: studied formal verification and contributed a parser fix to Tamarin Prover; currently writing a paper on OAuth security.
- Developer of Xsi, a Team Crescendo Discord bot with more than 100,000 registered users.
- Built Minecraft mods for Korean creators including Yangdding and Kim Jinu.
- Placed 40th at the 2025 ICPC Asia Seoul Regional Contest as team
GeongongiIsMae, solving 7 problems.
Full competition record
- Presidential Award (Silver Medal), University of Seoul Programming Challenge
- 40th Place, ICPC Asia Seoul Regional Contest, 2025 —
GeongongiIsMae, 7 solved - 5th Prize (Encouragement Award), Samsung Junior Software Development Contest, 2018
- 1st Prize, University-affiliated Gifted Education Mentorship Research Presentation Contest
- Encouragement Award, Korea Olympiad in Informatics (KOI) 1st Round, 2017–2019
- Bronze Medal, KOI 1st Round, 2020–2021
- Bronze Medal, KOI 2nd Round, 2020
- Encouragement Award, KOI 2nd Round, 2021
- Silver Medal, KOI 1st Round, 2022–2023
- Bronze Medal, KOI 2nd Round, 2022–2023
- Special Prize, Nexon Youth Programming Challenge (NYPC), 2019–2023
- Finalist, NYPC, 2022–2023
- Silver Medal, National Software Competition for High School Clubs, 2022
Portfolio · LinkedIn · self@ddayo.me