玄睿 / Rui

Rui

玄睿 · @Rui-727

about

// low level engineering

Rui here. I do low level engineering. Currently working on Ishizue (window server library, wlroots-style mechanism layer with a custom non-Wayland wire protocol). 2O9 (Arch Linux package manager), zenctl (hardware control library), and Hoshizora (PID 1 init) are all waiting on an issue. Also made RRSort (adaptive radix sort, O(n) when it can be) and gh-contribs (extract GitHub contribution data as flat text). :D

玄睿 Xuán Ruì / pinyin Gen Ei / romaji Rui

"The best thing that you can make is the one that you searched for it."

Rui

projects

Systems / Window Server Ishizue Window server library for Linux. Mechanism layer in the wlroots mold with a custom non-Wayland wire protocol. DRM/KMS atomic commits, libinput, libseat, dma-buf + drm_syncobj explicit sync, plane-slot model, headless test backend, separate-process X11 bridge speaking raw bytes. ~15k LOC, 4 integration tests passing.

C11LinuxDRM/KMSlibinputlibseat

Systems / Package Manager 2O9 Arch Linux package manager in C. Combines libalpm (vendored and modified), AUR workflow (chroot builds, PGP key import), and /nix/store/ with content-addressed paths, SQLite refs graph, hardlink dedup, and Ed25519-signed binary cache substitution. One config file (2O9.nix, Nix syntax). Includes Trakker (ptrace sandbox) and Debag (seccomp+ptrace hybrid sandbox with rizin-style static REPL and gdb-style live debugger).

C11Arch Linuxlibalpm/nix/storeNix

Systems / Init Hoshizora Minimal PID 1 init system for Linux. Single C file, libc only, static binary. Cgroups v2, fanotify, socket activation, sd-notify, plugin event socket, container integration. 2.7k LOC. 83 tests.

C99LinuxPID 183 tests

Systems / Logging hzlog Syslog collector. Binds /dev/log, prepends receive-time, appends to /var/log/messages. 97 lines of C. No rotation, no parsing, no deps.

Systems / Plugins hz-event-logger Example plugin for Hoshizora's event socket. Subscribe, filter by prefix, pipe matching events to a shell command. SIGCHLD=SIG_IGN, fdopen+fgets, no zombies.

C99Unix sockets

Systems / Session hz-session pam_exec helper for login session tracking. Writes session files, grants ACLs on GPU/sound/input devices, revokes on logout. 71 lines of shell.

POSIX shPAMsetfacl

Tool / Bookmarklet gh-contribs Extract GitHub contribution data as flat text. One line per day, sorted by date. Console paste, bookmarklet, or userscript. No dependencies, no network requests.

JavaScriptbookmarkletuserscript

Systems / Hardware zenctl C library and CLI that exposes every hardware control on Linux. 10 domains: CPU, memory, storage, network, GPU, thermal, power, PCIe, USB, firmware. sysfs + procfs + ioctl + ACPI/WMI + nl80211. NVML for NVIDIA, i915 for Intel. Typed domain API plus generic key-value fallback. 584 unit tests with mock sysfs.

C11Linuxsysfsioctllibrary

Algorithm / Sorting RRSort Ramanujan Radix Sort. Adaptive integer sort that is O(n) when max is polynomial in n, O(n log_n U) in general. Beats qsort by 2-7x on structured inputs. C11, static library, 31 tests, benchmarked up to 10M elements.

C11algorithmradix sortO(n)

hardware

MACHINE

Lenovo 500e Gen 2

Chromebook · 2019

OS

Arch Linux

linux-lts · sway

CPU

Intel N4100

4C · 1.1 GHz · Gemini Lake

RAM

4 GB LPDDR4

+ 8 GB zram (lz4)

skills

// languages

C99C++x86_64 asmLuaTerraPOSIX shPythonBash

// systems

Linux kernelcgroups v2fanotifysignalfdtimerfdUnix socketsELF-64x86_64 ABIPAM

// tools

gccmakegitQEMULFSArch Linuxcompiler designlinkers

contact & links

EmailRui-72x@protonmail.com