Systems Architecture

NixOS system configurations organized by hostname with shared modules in common/.

Channel Groups

Hosts use different nixpkgs channels. Changes to shared code (common/) must work across both channels.

Unstable (nixpkgs — nixos-unstable)

• okinawa — x86_64-linux, laptop / LLM build server (ASUS G14)
• kyushu — x86_64-linux, work laptop
• aomi — x86_64-linux, server
• sakhalin — x86_64-linux, home server

Stable (nixpkgs-25_11 — nixos-25.11)

• rhea — aarch64-linux, media server (main)
• aion — aarch64-linux, XMPP / podcast server
• athena — aarch64-linux, Raspberry Pi 4
• demeter — aarch64-linux, Raspberry Pi 4
• aix — aarch64-linux, Raspberry Pi 4
• kerkouane — x86_64-linux, VPS server
• carthage — x86_64-linux, VPS server

Host File Layout

Each host has a directory in /systems/<hostname>/ containing:

• boot.nix — bootloader, initrd, kernel modules
• hardware.nix — hardware-specific settings, filesystem mounts
• extra.nix (optional) — additional host-specific NixOS configuration
• home.nix (optional) — host-specific home-manager configuration

Build Verification

• Test current host: make build
• Test a specific host: make host/<hostname>/build
• Dry-build (eval only): make host/<hostname>/dry-build
• Direct nix: nix build .#nixosConfigurations.<hostname>.config.system.build.toplevel