⏻
Boot & initialization
Multiboot2, x86_64 long mode, GDT/IDT with a full exception set, PIT at 1000 Hz, Local + I/O APIC, and PS/2 keyboard & mouse drivers.
From-scratch · x86_64 · long mode
NyxOS
A 64-bit operating system written from scratch in C and x86_64 Assembly — a preemptive kernel, a windowed desktop with the Selene web browser and five games, a real TCP/IP stack, an EXT2 filesystem, and an in-OS C toolchain that self-hosts (a ported TinyCC + the xbm package manager) plus the native N language. No libraries. Just the metal.
◆ v6.4.180
LTS · v5.9.0
GPL-2.0+
0 build warnings
x86_64long mode · 4-level paging
C + NASMzero external libraries
57syscalls
TCP/IPDHCP · DNS · HTTP · poll()
32 windowscompositor + taskbar
EXT2read / write, auto-mount
cc + xbmself-hosting toolchain + packages
🌙 Nnative language · ncc
55 KATscrypto self-tests in CI
🌙 Seleneweb browser · real HTTP
5 gamesDOOM · Tetris · Snake · Pong · Mines
NX·SMEP·SMAPW^X · ring-3 isolation
Overview
An operating system you can read end to end
NyxOS boots via Multiboot2 (GRUB-compatible), enters long mode with 4-level paging, and provides a clean foundation for kernel development: a preemptive scheduler, ring-3 userspace with ELF64 and syscalls, a windowed GUI, and a from-scratch network stack — all built up one honest, verified increment at a time.
Features
What's inside the kernel
Every subsystem is written from scratch and verified in QEMU.
▤
Memory management
Bitmap physical allocator, a 16 MB kernel heap, 4-level paging with a higher-half mapping, per-process page tables, and NX + SMEP hardening.
⚙
Processes & scheduler
Preemptive weighted round-robin over kernel threads and ring-3 processes, with full shell job control — exec, spawn, jobs, wait, kill, nice.
◈
ELF userspace
An ELF64 loader, an embedded initramfs, fork() with copy-on-write, 57 syscalls via syscall/sysret, a minimal libc, and isolated per-process file descriptors — a real ring-3 environment.
⚒
In-OS C toolchain
A ported TinyCC compiles C inside NyxOS and self-hosts — tcc compiles tcc. The cc command builds & runs C by bare name, and xbm — the package manager — compiles a recipe and installs it to /mnt/bin.
🌙
N & N++ languages
NyxOS's own languages: N (.n, built with ncc) and the typed superset N++ — HolyC-style, first-class, compiled in-OS. xbm install ncc builds the N compiler on the machine itself.
❯
Shell
40+ built-in commands with Tab completion, environment-variable expansion, command history, I/O redirection, pipelines, job control (exec/spawn/jobs/wait/kill), and nice/renice priority control.
🖧
Networking
RTL8139 driver, ARP/IPv4/UDP/ICMP/DHCP/DNS, and a full TCP stack: retransmission with RTO, passive open (listen/accept), loopback, an HTTP client & server, nc full-duplex, and poll() I/O multiplexing.
🗔
GUI compositor
Up to 32 windows with z-ordering, drag & resize, four workspaces, drop shadows, snap-to-edge with a live preview, a taskbar and Start menu — plus a Terminal, File Manager, Text Editor, Image Viewer, Paint, Calculator, Settings and Sound Test, each with its own hand-drawn icon.
◨
Desktop & rendering
A polished 1080p desktop with animated wallpapers (/lava, /matrix, /fire) and real-time render testbeds — Nyx Voxels and Nyx Fractal — with on-screen benchmark HUDs. Fluid, personal, unmistakably Nyx.
🌙
Selene — web browser
NyxOS browses the real internet: Selene resolves DNS, opens a TCP connection and fetches a page over HTTP, then strips the HTML to text and word-wraps it under a URL bar. DHCP, chunked-transfer decoding and scrolling included. Named for the moon goddess.
🎮
Games
A desktop Games folder with five: the original 1993 DOOM (running in a window), Minesweeper, Pong, Snake and Tetris — the last three animated in-kernel by a ~30 fps compositor game-tick.
🖴
Filesystem
A ramdisk VFS with an EXT2 read/write driver auto-mounted at /mnt, a write-through sector cache, per-fd byte offsets, and persistence across reboots on a disk image.
♪
Multimedia
A Bochs VBE framebuffer (1024×768×32), a Sound Blaster 16 driver (DMA + IRQ + mixer), PC-speaker tones, and the original DOOM engine ported to run on the framebuffer.
🛡
Security & isolation
NX + SMEP + SMAP and W^X page permissions, per-process address spaces, a hardened syscall boundary (bounded ELF loads, validated user pointers), ring-3 fault isolation — a crash kills the process, not the kernel — and PBKDF2-HMAC-SHA256 login, backed by a from-scratch crypto library verified by 55 known-answer tests in CI.
Architecture
How it fits together
A higher-half kernel, isolated user address spaces, and an interrupt-driven core.
Boot flow
- GRUB / Multiboot2 hands off with a memory map + framebuffer.
- Long mode — GDT, 64-bit code/data, TSS, IDT with IST stacks.
- Paging — identity-map low memory, mirror the kernel into the higher half.
- Drivers — PIT, APIC, PS/2, RTL8139, ATA/EXT2, VBE, SB16.
- Login — PBKDF2-hashed credentials (nyx / nyx).
- Desktop — the window compositor launches as a scheduled process.
Memory layout
0xFFFFFF80_00000000Higher-half kernel (PML4[511])
0x00000000_00100000Kernel linked low (1 MB)
user halfPer-process, isolated (no identity map)
NX + SMEPUser pages non-exec; kernel can't run user code
Interrupt core
The PIT (ISA IRQ0) is routed via the I/O APIC on pin 2 → vector 32, driving a 1000 Hz tick. The scheduler preempts on that tick; syscalls and IRQs switch CR3 on entry so each process sees only its own address space.
Manual
Getting started
Build the kernel, boot it in QEMU, and log in.
1
Clone & build
# cross-compiler (x86_64-elf-gcc) or host gcc -m64
git clone https://github.com/kazah-png/nyx-os.git
cd nyx-os
make -C kernel # → kernel/nyx-kernel.bin.\build.ps1 # WSL cross-compile → kernel + bootable ISO
2
Run in QEMU
# GUI desktop + networking + disk
qemu-system-x86_64 -cdrom NyxOS.iso -m 256M -no-reboot \
-hda ext2-test.img -nic user,model=rtl8139 -display sdlServe HTTP from the guest by forwarding a host port: add hostfwd=tcp::8080-:80 to the NIC, run tcpserve 80, then curl localhost:8080.
3
Log in
The boot animation leads to a framebuffer login screen. The default account is nyx / nyx (PBKDF2-HMAC-SHA256). On success, the NyxOS Desktop launches; with no disk, it falls back to a text shell.
Command reference
The built-in shell — also available in the Terminal window.
| Category | Commands |
|---|---|
| System | help clear nyxfetch uname date version reboot history env export |
| Files | ls cd pwd cat touch mkdir rm cp mv head tail grep sort wc find tree write which diff hexdump |
| Processes | ps mem exec spawn jobs wait kill nice renice usertest pmap free |
| Toolchain | cc xbm ncc tcc · compile & run C in-OS; xbm install <pkg> builds a recipe into /mnt/bin |
| Network | ifconfig dhcp ping setip httpget tcptest tcpdrop tcploop tcpserve nc |
| Apps & games | selene doom pong snake tetris · plus a desktop icon for each & a Games folder |
| Filesystem | mount · EXT2 auto-mounts at /mnt |
| Graphics & sound | gui desktop mode fonttest beep play sb16play |
Networking
A real TCP/IP stack
From the NIC driver up to an HTTP server — every layer written and debugged from the wire.
HTTP · DNS · Selene · ncweb browser, client, server, full-duplex poll()
TCPretransmit (RTO) · listen/accept · userspace sockets
UDP · ICMPdatagrams · userspace sockets · echo (ping) with RTT
IPv4checksum · routing · loopback delivery
ARP · Ethernetcache · frames
RTL8139PCI NIC · TX/RX rings
Highlights
- 🌙 Selene web browser — resolves DNS, connects over TCP and fetches a real page by HTTP, decodes chunked transfer encoding, and renders the HTML to scrollable text under a URL bar.
- DHCP client — DISCOVER → OFFER → REQUEST → ACK, auto-configures IP, netmask & gateway.
- ping with statistics — real round-trip timing, per-packet sequencing, and a min/avg/max + loss summary. NyxOS also answers echo requests.
- TCP retransmission — each connection buffers its outstanding segment and resends it on an RTO with exponential backoff; a lost SYN or data segment recovers automatically.
- Passive open — listen/accept spawn per-client connections. tcpserve answers a real curl from the host with HTTP/1.1 200 OK.
- Userspace sockets — socket/connect/sendto/recvfrom/bind/listen/accept for both TCP and UDP from ring 3.
- poll() I/O multiplexing — SYS_POLL (syscall 43) waits on sockets, pipes, and stdin with timeout. Powers full-duplex nc.
- nc (netcat) — full-duplex TCP/UDP client and TCP server, bridging stdin/stdout via poll().
- Loopback — a self-contained 127.0.0.1 path lets the whole stack be tested in-guest (tcploop, ping 127.0.0.1).
Releases
The road so far
Every increment from a from-scratch kernel to a networked desktop OS with a web browser and five games.
v1.x
Foundations
Base kernel, ramdisk VFS + shell commands, and the first real networking (RTL8139, ARP/IP/UDP/ICMP).
v2.x
Multitasking, GUI & disks
Preemptive multitasking, a full TCP stack, the window compositor, PC-speaker audio, EXT2 read support, and a Sound Blaster 16 driver.
v3.x
Userspace
ELF loader, initramfs, per-process paging, ring-3 execution, syscalls, an RTC driver and a minimal libc.
v4.x
64-bit & hardening
Full x86_64 long mode, a higher-half kernel, user/kernel page-table isolation, and NX + SMEP with APIC init.
v5.0–5.7
Apps, login, ring-3 & the network arc
A full GUI app suite, a boot animation + login screen, syscall-boundary hardening, ring-3 userspace that actually runs, preemptive scheduling with job control, and a networking sprint — loopback + ICMP, TCP retransmission, passive open, and an HTTP server that answers real clients.
v5.8
A complete ring-3 environment
The native language runtime, waitpid(), anonymous pipes & blocking IPC, signals with setjmp/longjmp recovery, poll() I/O multiplexing, nc, persistent EXT2 accounts, and the root-cause fix of the pipeline-corruption Heisenbug (a firmware-hole page-allocator bug).
v5.9.0 · LTS
The stable baseline — P0.1 closed
The one release-blocking bug root-caused and fixed with a single cli, closing the preemptible window between the user-CR3 reload and iretq. Plus a GUI/VFS/ext2 hardening sweep and the first SMP stages (per-CPU TSS, spinlocks, TLB-shootdown IPIs). The long-term-support release.
v5.9.x
"Nightfall" desktop · DOOM · five games · Selene
A central GUI palette in brand purple, modern window chrome (shadows, gradients, rounding), keyboard window management & snapping. The original 1993 DOOM ported and playable in a window, joined by Tetris, Snake, Pong and Minesweeper. And 🌙 Selene — the NyxOS web browser — fetches and renders real pages over DHCP + DNS + TCP + HTTP.
v6.0–6.1
daedalOS pivot — Phase 1: the desktop
The push toward a fully-functional daedalOS-style desktop OS: a polished 1080p desktop, visual file management, a Windows-like clean menu, and multi-session groundwork — all keeping the Nyx night-goddess identity.
v6.2–6.3
Phase 2: an in-OS C toolchain that self-hosts
TinyCC 0.9.27 ported to run inside NyxOS — tcc compiles tcc. The cc command and the xbm package manager compile C from a recipe and install it to /mnt/bin, runnable by bare name. The everyday install/remove/update/search/list verb set is complete.
v6.4.180
Languages, IRQ-driven networking & render testbeds — current
The native N language (.n / ncc) and the typed superset N++ with static checks; RTL8139 moved toward interrupt-driven RX/TX with a real retransmit queue and SMP-safe TCP; the Nyx Voxels and Nyx Fractal render benchmarks and animated wallpapers; AES Key Wrap (RFC 3394) landing a 55-KAT crypto battery in CI; and a steady security issue burn-down — one honest, verified increment at a time.
Follow the build
NyxOS is developed in the open, one verified increment at a time. Join the Discord for kernel-dev chat, or dive into the source and status report on GitHub.