NixCon 2023

If you ask three NixOS users what their favorite NixOS deployment tool to update a NixOS system is, you might get four answers. However, installing NixOS on a machine can be a tedious and manual process, especially if the machine is not physically accessible or does not have a NixOS installer. In this talk, we will introduce two tools that can simplify and automate the installation of NixOS on any machine with Linux and SSH access: disko and nixos-anywhere.

Disko is a declarative disk partitioning tool that allows you to specify the layout of your disks using a simple Nix expression. It can create, resize, format, and mount partitions on any device that supports block operations. It also supports encryption, ZFS, RAID, and LVM.

Nixos-anywhere is a tool that can install NixOS on any cloud or bare-metal environment over SSH. It can detect whether the target machine has a NixOS installer; if not, it can use kexec to boot into one. It then uses disko to partition and format the disks according to your configuration, and installs NixOS with your desired packages and secrets.

With these tools, you can easily deploy NixOS on any machine without needing physical access or manual intervention. You can also reuse the same configuration for multiple machines, ensuring consistency and reproducibility.

In this talk, we will demonstrate how to use disko and nixos-anywhere to install NixOS on various scenarios, such as a virtual machine, laptops or bare-metal servers. We will also discuss some of the challenges and limitations of these tools, and how they can be improved in the future.