--- title: "Nix Home Manager" date: "2022-09-19T21:49:46+02:00" author: "$HUMANOID" tags: ["nix", "linux"] description: "Basics of using the Nix Home Manager in a way that makes sense to me and probably just me" draft: false toc: true --- # The Home Manager The Nix Home Manager is a way to work with Nix in a declarative environment to manage your dotfiles and user environment packages. This can be used on any system running the Nix packagemanager. Personally, I've started to dabble around with it a bit after installing the Nix packagemanager in my Alpine installation. Since I've already dabbled with Nix on a few systems through NixOS, I already knew the basics of functionally managing packages (or derivations) with the Nix packagemanager. Hence I really quickly got sick of installing packages the imperative way. After looking around for a bit, I found some post mentioning that managing packages in a functional environment outside of NixOS is a bit of a hack. The post referred to some other sources, one of which used a custom meta package and another referred to the [Home Manager](https://nix-community.github.io/home-manager/). I had messed around with the Nix Home Manager a tiny bit before, but never _really_ gave it a chance to shine as I didn't really understand it. This time around, I decided to look up some tutorials and see how it worked. When going through the instructions of either tutorial I used, I quickly came to the realisation why I had never _really_ looked at it. Both tutorials took a lot of unnecessary steps according to the author's will and assumed that everyone following their tutorials had the same preferences as them. I obviously don't. So here's my take on installing the Home Manager outside of NixOS. # Actually using Home Manager Assuming you're continuing from [my previous article on Nix](/rambles/nix-on-other-distros-packagemanagers), the first step is to go to the Home Manager github page and go to the [page regarding the standalone installation](https://nix-community.github.io/home-manager/index.html#sec-install-standalone). From there, things will be quite self explanatory if you're used to the (bare) basics of NixOS. Though instead of using `/etc/nixos/configuration.nix` you'll be using `$HOME/.config/nixpkgs/home.nix` by default. A basic Home Manager installation will leave you with a `home.nix` file with the following content: ```nix { config, pkgs, ... }: { # Home Manager needs a bit of information about you and the # paths it should manage. home.username = "$USER"; home.homeDirectory = "/home/$USER"; # This value determines the Home Manager release that your # configuration is compatible with. This helps avoid breakage # when a new Home Manager release introduces backwards # incompatible changes. # # You can update Home Manager without changing this value. See # the Home Manager release notes for a list of state version # changes in each release. home.stateVersion = "22.05"; # Let Home Manager install and manage itself. programs.home-manager.enable = true; } ``` After making any changes to your `home.nix` file, you can apply them with: ```sh home-manager switch ``` If you first want to see whether you build is going to be successful or not, run: ```sh home-manager build ``` ## Installing packages To add some packages, you'll need to add them to the `home.packages` array. On my Alpine installation I have the following: ```nix ... home.packages = with pkgs; [ brave vscodium ]; ... ``` Notice the `with pkgs;` section. This prevents you from having to add the `pkgs` prefix to every package you want to add. I don't think this is the idiomatic way of adding packages to your configuration, but it allows me to be a bit lazier and it hasn't caused any breakages yet. ## Managing dotfiles and configuration Another amazing thing the Home Manager can do is manage your dotfiles. And this in turn can be managed with Git. More on this later. ### Git configuration For instance, I have it manage my Git config using the git module. To do this, I have the something like the following in my `home.nix`: ```nix ... programs.git = { enable = true; ignores = [ "*.swp" ]; # I don't need to see that I still have a file open in vim signing = { key = ""; signByDefault = false; # it would probably be better for security to have this be true, but doing so gets annoying really fast }; userEmail = ""; userName = ""; extraConfig = { init = { defaultBranch = "main"; }; }; }; ... ``` Here's the [list of options](https://nix-community.github.io/home-manager/options.html#opt-programs.git.enable) supported by the git module. I _strongly_ recommend digging through the documentation, looking for things that interest you in your current situation and setup. ### Integrating existing (dot)files The Home Manager can also manage arbitrary (dot)files for you. I have it link my `.zshrc` into place with the following line: ```nix ... home.file.".zshrc".source = ./zshrc; ... ``` This looks for a file called `zshrc` in the same directory as `home.nix`. From there, it symlinks it to `~/.zshrc` It can also manage recursive file structures. I have it keep track of my `sxiv` configuration with the following few lines: ```nix ... home.file.".config/sxiv" = { source = ./sxiv; recursive = true; }; ... ``` The interesting portion of this snippet is the `recursive` boolean. Because of this, Home Manager will recreate the directory structure found in `./sxiv` in `~/.config/sxiv` and symlinks the files found inside into place. # Git integration Since all the Home Manager requires is (at least) a single text file to manage your dotfiles and Nix environment packages, it's really easy to keep track of your configuration using Git. To that end, I have a bare repository on one of my home servers over at `/srv/git/nix/.git` As a remote, I have pointed my repo in `$HOME/.config/nixpkgs/` to `:/srv/git/nix/.git`. This works over ssh. My `$HOME/.ssh/config` contains the following lines to make the preceding work: ```ssh Host Hostname User git Identityfile ~/.ssh/ Port 4242 IdentitiesOnly yes # this makes using an ssh agent a bit easier when using multiple keys on the same host ```