NixOS Container Management

# Container Management {#ch-containers} NixOS allows you to easily run other NixOS instances as *containers*. Containers are a light-weight approach to virtualisation that runs software in the container at the same speed as in the host system. NixOS containers share the Nix store of the host, making container creation very efficient. ::: {.warning} Currently, NixOS containers are not perfectly isolated from the host system. This means that a user with root access to the container can do things that affect the host. So you should not give container root access to untrusted users. ::: NixOS containers can be created in two ways: imperatively, using the command `nixos-container`, and declaratively, by specifying them in your `configuration.nix`. The declarative approach implies that containers get upgraded along with your host system when you run `nixos-rebuild`, which is often not what you want. By contrast, in the imperative approach, containers are configured and updated independently from the host system. ```{=include=} sections imperative-containers.section.md declarative-containers.section.md container-networking.section.md ```

NixOS enables running other NixOS instances as lightweight containers, which share the host's Nix store for efficient virtualization. A critical warning notes that these containers are not perfectly isolated, meaning root access within a container can impact the host system and should not be granted to untrusted users. Containers can be managed either imperatively via the `nixos-container` command, allowing independent configuration and updates, or declaratively in `configuration.nix`, which results in them being upgraded alongside the host system.