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Multi-host

One user-packages repo can describe any number of machines. Each host has its own subdirectory under hosts/, its own manifest, and its own [settings] (including system tuple and primary user).

See ADR-005 for the design rationale.

Layout​

~/.config/glixos/
├── flake.nix
├── flake.lock
├── hosts/
│   ├── laptop/
│   │   ├── default.nix
│   │   └── glix.toml          # x86_64-linux, alice
│   ├── desktop/
│   │   ├── default.nix
│   │   └── glix.toml          # x86_64-linux, alice
│   └── pi/
│       ├── default.nix
│       └── glix.toml          # aarch64-linux, pi-user
└── shared/                    # optional, your own modules
    └── base.nix

Adding a host​

glix init --host=desktop --user=alice --system=x86_64-linux
glix init --host=pi --user=pi-user --system=aarch64-linux

glix init is host-additive: it leaves existing hosts alone and registers the new one in the glix-managed hosts region of flake.nix.

Operating on a specific host​

Every read and write command takes --host:

glix add --host=pi --scope=system raspi-firmware
glix list --host=desktop
glix show --host=pi raspi-firmware
glix rebuild --host=desktop switch

If you omit --host, the default is $(hostname) on the current machine.

Listing across hosts​

glix list --all-hosts
HOST     NAME       SCOPE   STATE    USER   FLAKE
desktop  firefox    system  enabled         github:NixOS/nixpkgs#firefox
laptop   firefox    system  enabled         github:NixOS/nixpkgs#firefox
laptop   greeting   home    enabled  alice  github:owner/pkg-greeting
pi       raspi-fw   system  enabled         github:owner/raspi-firmware
glix info
hosts:
  desktop      system=x86_64-linux primary_user=alice    packages=12/14 enabled
  laptop       system=x86_64-linux primary_user=alice    packages=10/11 enabled
  pi           system=aarch64-linux primary_user=pi-user packages=3/3   enabled

Sharing modules​

Anything outside hosts/<host>/ is yours to organise. A common pattern is a shared/ directory imported from each host's default.nix:

# hosts/laptop/default.nix
{ ... }:
{
  imports = [ ../../shared/base.nix ];
  networking.hostName = "laptop";
  # ...
}
# shared/base.nix
{ pkgs, ... }:
{
  time.timeZone = "America/Los_Angeles";
  environment.systemPackages = with pkgs; [ git tmux ];
}

glix never edits shared/ or the parts of hosts/<host>/default.nix outside the glix-managed regions of flake.nix. Everything is yours to refactor.

Building a remote host​

nixos-rebuild supports --target-host and --build-host. Pass them through your usual NixOS workflow; glix only owns the manifest side.

nixos-rebuild switch --flake .#pi --target-host root@pi.local

Mixing architectures​

The Nix system tuple lives in each host's [settings] system. glix init writes it; you can change it later by editing glix.toml directly (no mutation flag yet) and running any glix command to trigger a flake regen.