feat(docs): Improving documentation c:

docs/src/SUMMARY.md

@@ -1,4 +1,5 @@
 # Summary
 
-- [NixOS Module Options](./nixos-options.md)
-- [Home Manager Module Options](./home-options.md)
+- [Nix Based Configuration](./configuration-overview.md)
+    - [NixOS Module Options](./nixos-options.md)
+    - [Home Manager Module Options](./home-options.md)

docs/src/configuration-overview.md

@@ -0,0 +1,88 @@
+# Nix Based Configuration
+
+I use [NixOS](https://nixos.org) and
+[home-manager](https://github.com/nixos-community/home-manager) to manage my
+system and user configuration respectively. You can see what options I have
+added to configure the system and user configuration in the next chapters.
+
+## How to Use
+
+If you are not me, then you probably shouldn't use this, but feel free to draw
+inspiration from what I have done c:.
+
+First you want to see what your environment is; if you are using NixOS then you
+want to look at the [NixOS Module Setup](#nixos-module-setup), if you are just
+using home-manager, then you should look at the [homa-manager Module
+Setup](#home-manager-module-setup).
+
+### NixOS Module Setup
+
+> Although I am talking about the NixOS module setup, this uses both NixOS and
+> home-manager, so you can (and should) use both modules.
+
+#### Setup from LiveISO
+
+Follow the [NixOS Manual](https://nixos.org/manual/nixos/stable) until before
+you run `nixos-generate-config`.
+
+First you will want to create a directory for your NixOS configuration. I like
+using `~/.config/nixos`. You then want to run `nixos-generate-config --root /mnt
+--dir ~/.config/nixos` (assuming you mounted your filesystem to `/mnt`). Now you
+have `configuration.nix` and `hardware-configuration.nix` inside
+`~/.config/nixos`. I like renaming `configuration.nix` to `default.nix` and
+putting it in a folder with the same hostname as the machine (See [the source
+repo](https://github.com/jalil-salame/configuration.nix/tree/main/machines)).
+
+Now you can add a `flake.nix` file to your `~/.config/nixos` and make it a flake
+based configuration. This is the general structure you'll want:
+
+```nix
+{
+  inputs.nixpkgs.url = "nixpkgs/nixos-unstable";
+  # My custom configuration module
+  inputs.config.url = "github:jalil-salame/configuration.nix";
+  inputs.config.inputs.follows.nixpkgs = "nixpkgs";
+
+  outputs = { self, nixpkgs, config }: let
+    pc = import (./. + hostname);
+    hostname = "nixos";
+    system = "x86_64-linux";
+    overlays = builtins.attrValues config.overlays;
+    config.allowUnfreePredicate = pkg: builtins.elem (lib.getName pkg) [
+      "steam-original"
+    ];
+    pkgs = import nixpkgs { inherit system overlays config; };
+  in {
+    nixosConfigurations.${hostname} = nixpkgs.lib.nixosSystem {
+      inherit system pkgs;
+      modules = [
+        # My configuration module (includes home-manager)
+        config.nixosModules.nixosModule
+        # Results from `nixos-generate-config`
+        pc
+        # Custom options (see module configuration options)
+        {
+          # Enable my custom configuration
+          jconfig.enable = true;
+          jconfig.gui.enable = true; # Enable gui environment
+
+          # Add users to use with home-manager
+          users.users = {};
+
+          # Add home-manager users configuration (here you can enable jhome options)
+          home-manager.users = {};
+          # home-manager globally set options
+          home-manager.sharedModules = [{ jhome.hostName = hostname; }];
+        }
+      ];
+    };
+  };
+}
+```
+
+### home-manager Module Setup
+
+If you are not using NixOS, then you probably want to only use the home-manager
+configuration. In that case, you want to use the
+`nixosModules.homeManagerModuleSandalone` in your `home-manager` configuration,
+and probably disable GUI applications all together `jhome.gui.enable = false`.