Host Discovery

Hosts are auto-discovered from the filesystem. No manual registration in flake.nix is needed.

macOS Hosts (easy-hosts)

easy-hosts scans hosts/<arch>-darwin/<hostname>/ directories and generates darwinConfigurations entries automatically.

hosts/
├── aarch64-darwin/
│   └── USMBDEROSER/        ← auto-discovered as darwinConfigurations.USMBDEROSER
│       ├── default.nix     ← system config (required)
│       ├── user.nix        ← username + email (required)
│       └── home.nix        ← per-host HM overrides (optional)
└── x86_64-darwin/
    └── <hostname>/
        ├── default.nix
        ├── user.nix
        └── home.nix

The default.nix must import user.nix and wire up _module.args and home-manager.extraSpecialArgs so the username is available throughout the config. See Adding a Host for the full walkthrough.

Linux Hosts (custom discovery)

Linux hosts use a similar directory convention under systems/:

systems/
├── x86_64-linux/
│   └── <hostname>/
│       ├── system.nix      ← system-manager config
│       ├── user.nix        ← username + email
│       └── home.nix        ← per-host HM overrides (optional)
└── aarch64-linux/
    └── <hostname>/
        └── ...

easy-hosts assumes all *-linux directories are NixOS, but these are Ubuntu machines using system-manager. So flake.nix contains custom logic to scan systems/ and generate systemConfigs + homeConfigurations.

Why Two Directories?

The split between hosts/ (Darwin) and systems/ (Linux) exists because easy-hosts would try to create NixOS configurations for Linux directories under hosts/. Keeping them separate avoids this conflict.

Branch Strategy

Host directories are typically developed on feature branches named host/<hostname> and merged to main once tested. This keeps main clean while allowing per-machine iteration.