NixOS as a daily driver or Zero to Nixty, part 4/? - dotfile/config management

Published June 27, 2025

5 min read

Tags: nixos, linux

From TTY to Tiling

In the last post, we enabled Hyprland and set it to run by default on login.

In this post, we will be taking a slight detour and will be going over how to manage your NixOS config in version control. This step might be overkill for some but it makes it so we can easily checkout our config on any machine and have a working NixOS install fairly quickly.

We will also cover a little Hyprland config at the end.

Introducing Dotter

Dotter is a dotfile manager and templater.

You have a repo of dotfiles and two main config files:

.dotter/global.toml

• global config where you define "modules" and tell Dotter how to handle copying config.
• commit to version control

.dotter/local.toml

• Per machine file that tells dotter which config to load. The idea being you may have different config needs for linux, macos, or windows.
• This file is not committed to git because local lets you switch configs per machine without affecting version control

Add a .gitignore if not already present. Add a new line: .dotter/local.toml

After configuring everything, you simply run dotter deploy and the config files are copied to the locations set in global.toml.

It's a great project and I highly recommend it.

Moving NixOS Config to Dotfiles Repo

The first thing we'll do is add a new directory in our dotfile repo. Then we'll need to open up our .dotter/global.toml file and add our NixOS config paths. That looks like this for me:

[nixos.files]
nixos = '/etc/nixos'

In Dotter talk, this is setting up a "module" named nixos. We are telling Dotter that this module's files will be located in the nixos folder and need to be copied to /etc/nixos.

Now you will need to move the current NixOS config from /etc/nixos/configuration.nix to your new nixos folder.

One other step will be to allow writes to your /etc/nixos dir by running sudo chmod o+w /etc/nixos.

One important configuration option to mention for Dotter is the default_target_type. Because of the template functionality of Dotter, it can either physically copy your config, or simply create a symlink.

I prefer symlinks by default so I use this config option. In global.toml, I set the following:

[settings]
default_target_type = 'symbolic'

More info about that can be found in the Dotter wiki.

If you plan to use symlinks with Dotter, you will need to open up nixos/configuration.nix and make the hardware-configuration.nix import an absolute path instead of relative path.

Example:

# nixos/configuration.nix
{ config, pkgs, ... }:

{
  imports =
    [ /etc/nixos/hardware-configuration.nix ];
}

You will also need to add your .dotter/local.toml file.

That will look something like this:

packages = [
  'cmus',
  'git',
  'hypr',
  'nvim',
  'nushell',
  'starship',
  'waybar',
  'wezterm',
  'wofi'
]

This is telling Dotter which of the "packages" in your global.toml should be copied. This helps allow us to define our complete config in one repo even if every host doesn't use every package. Each host will have a local.toml that copies specific packages.

Now it's finally time to run dotter deploy. This will do the important step of taking our local dotfiles and copying (or symlinking) to the dirs we specified. After running that command, you will see /etc/nixos/configuration.nix is present again.

The moment of truth, time to rebuild. You can start by doing a dry run sudo nixos-rebuild dry-activate. This will build the system and tell you what would happen. If that goes well, run sudo nixos-rebuild switch. NixOS gives a lot of protection around broken config so it's unlikely anything should break here and if it does, there will be an error that tells you why.

Commit your configuration file and merge your branch back to main.

Adding Hyprland Config to Dotfiles Repo

We are now going to do the same with our Hyprland config. The steps are pretty much the same minus some chmod and file path updates.

First, create a new branch and check it out. Then we create a new directory that I simply called hypr. Next, copy the current Hyprland config from ~/.config/hypr into this new dir.

Now we will need to add a little Dotter config:

[hypr.files]
hypr = '~/.config/hypr'

Again, in Dotter talk, we are creating a hypr module. Then we tell Dotter that any files in our local hypr dir need to be copied to ~/.config/hypr.

Now it's time to run dotter deploy. This will do the step of copying our local config to the correct path in ~/.config.

Confirm that file got copied and then run hyprctl reload to reload the hypr config.

Congrats On Version Controlled Config

Your dotfile repo should now look something like this:

dotfiles/
├── .dotter/
│   ├── global.toml
│   └── local.toml
├── hypr/
│   └── hyprland.conf
└── nixos/
    └── configuration.nix

We have now added two sets of our config into version control. This will allow us to easily pass around our config to a new machine if needed, especially with NixOS and it's declarative config.

Next Time

In the next post, I plan to get back to actually setting up NixOS for daily driver use. This will probably include some hypr config and introducing Nixvim. Nixvim is a way to manage your neovim plugins in a NixOS-y way.