Hi, I'm Jihoo.

I'm Jihoo — an undergraduate who lives and breathes systems-level code. My main languages are Rust, C++, C, and Astro, and I'm happiest when I'm deep in a compiler or poking around inside an operating system kernel. You can find me on GitHub.

My day-to-day machines both run NixOS with niri and noctalia shell — laptop and desktop, same setup. Nix is more than a package manager to me; it's how I think about reproducibility and system design. Beyond that, I'm fascinated by compilers and language implementation, AI agents and how they're reshaping the way we write software, Lisp and its family of languages, and Cubical type theory — which sits at this beautiful intersection of type theory, homotopy theory, and constructive mathematics that I find endlessly compelling. Outside of code, I enjoy dabbling in philosophical thinking — nothing rigorous, just casual reading around East Asian traditions like Buddhism and Taoism, and lately Plato's ideas too. There's something about impermanence and non-duality on one side, and the theory of Forms on the other, that feels oddly resonant with how I think about types and computation.

I reach for an AI agent constantly while coding.

One project I'm particularly proud of is cuviz — a cubical type theory visualizer written in Rust. It parses and typechecks cubical lambda terms, normalizes them via NbE, and renders the AST as an interactive tree with step-by-step reduction traces and geometric/topological diagrams — think path types, squares, HITs like S¹, transport, and Glue types, all rendered live through a React/D3 frontend. Under the hood it's got a full cubical backend with universe cumulativity, hcomp decomposition, and a bidirectional typechecker. It also doubles as the cubical backend for Hokkaido, a programming language I'm also working on.

On the OS side, I'm building KaguyaOS — a hobby OS written in Rust targeting x86_64 UEFI. It boots via UEFI with a GOP framebuffer, enforces ring 0/3 isolation with 25 system calls, runs a cooperative round-robin scheduler with SMP support, and has drivers for xHCI USB, NVMe SSD, and E1000 Ethernet. There's a FAT16 filesystem and a shell to tie it all together.

I've also been building Albireo — a hardware-accelerated 3D voxel visualizer for infinite-dimensional data, built with Rust and wgpu. It maps each point's dimension, position, and a disambiguation layer onto x/y/z coordinates as solid, alpha-transparent voxel cubes, with an orbit camera and a builder API for constructing scenes. Named after the Albireo star — just because I like it.