Nixstrap is a GCP image that is designed to be deployed as an initial bootstrap, to pull in a NixOS closure stored in a separate binary cache. This improves bringing up new GCP instances, bringing it closer to updating an existing system.
The information necessary for downloading the NixOS system closure is stored in instance metadata keys:
-
nixstrap-system: the path of the NixOS closure, e.g./nix/store/wj2y92z38gbkjdi68ipfbc5011hhlxj0-nixos-system-unnamed-20.09pre-git -
nixstrap-keys: A list of Ed25519 keys (innix.confformat) that are to be trusted, e.g.cache.nixos.org-1:6NCHdD59X431o0gWypbMrAURkbJ16ZPMQFGspcDShjY= -
nixstrap-substituters: A list of additional substituters that will be queried for store paths, e.g.https://cache.nixos.org/
Once the installation is done, a key is set in the guest attributes of
the instance, in nixstrap/status. If success, the install succeeded
and the VM is running the NixOS system. If fail, something went wrong
and the serial logs can probably be queried to see what happened.