doc: Add example flake

example/flake.nix

@@ -0,0 +1,39 @@
+{
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/nixpkgs-unstable";
+    tf2-nix.url = "path:///home/crumb/src/tf2-nix";
+  };
+
+  outputs = { self, ... }@inputs: {
+    # TF2 config built as a package.
+    packages.x86_64-linux.default =
+      let
+        pkgs = import inputs.nixpkgs { system = "x86_64-linux"; };
+        tf2pkgs = inputs.tf2-nix.packages.x86_64-linux;
+      in tf2pkgs.mergeTf2Configs (with tf2pkgs; [
+        mastercomfig.presets.medium-low
+        mastercomfig.addons.flat-mouse
+        mastercomfig.addons.no-tutorial
+        mastercomfig.addons.null-canceling-movement
+        maps.jump_beef
+        improved-crosshairs
+        loadouts-script
+        # Packages are overridable.
+        (huds.deerhud.overrideAttrs (final: prev: {
+          patches = [ ./raise-uber-meter.patch ];
+        }))
+        # Existing configs on your file system may be referenced by path:
+        ./my-config
+      ]);
+
+    # TF2 config installed using Home-manager.
+    homeConfigurations.default =
+      let gameDir = ".local/share/Steam/steamapps/common/Team Fortress 2/tf";
+      in {
+        home.file.${gameDir} = {
+          recursive = true;
+          source = self.packages.x86_64-linux.default;
+        };
+      };
+  };
+}

example/my-config/cfg/overrides/autoexec.cfg

@@ -0,0 +1 @@
+echo "Hello!!!!!!!!!!!!!!!!!!!"

example/raise-uber-meter.patch

@@ -0,0 +1,49 @@
+diff --git a/resource/ui/hudmediccharge.res b/resource/ui/hudmediccharge.res
+index afbf45a..5b0cd3c 100644
+--- a/resource/ui/hudmediccharge.res
++++ b/resource/ui/hudmediccharge.res
+@@ -5,7 +5,7 @@
+ 		"ControlName"	"ImagePanel"
+ 		"fieldName"		"MeterBrackets"
+ 		"xpos"			"cs-0.5"
+-		"ypos"			"47"
++		"ypos"			"3"
+ 		"zpos"			"-5"
+ 		"wide"			"156"
+ 		"tall"			"20"
+@@ -21,7 +21,7 @@
+ 		"ControlName"	"CExLabel"
+ 		"fieldName"		"ChargeLabel"
+ 		"xpos"			"cs-0.5"
+-		"ypos"			"50"
++		"ypos"			"6"
+ 		"zpos"			"3"
+ 		"wide"			"90"
+ 		"tall"			"15"
+@@ -65,7 +65,7 @@
+ 		"ControlName"	"CExLabel"
+ 		"fieldName"		"IndividualChargesLabel"
+ 		"xpos"			"c92"
+-		"ypos"			"44"
++		"ypos"			"0"
+ 		"zpos"			"2"
+ 		"wide"			"90"
+ 		"tall"			"30"
+@@ -87,7 +87,7 @@
+ 		"fieldName"		"ChargeMeter"
+ 		"font"			"Default"
+ 		"xpos"			"cs-0.5"
+-		"ypos"			"50"
++		"ypos"			"6"
+ 		"zpos"			"2"
+ 		"wide"			"150"
+ 		"tall"			"14"				
+@@ -107,7 +107,7 @@
+ 		"fieldName"		"ChargeMeter1"
+ 		"font"			"Default"
+ 		"xpos"			"c-75"
+-		"ypos"			"52"
++		"ypos"			"8"
+ 		"zpos"			"2"
+ 		"wide"			"36"
+ 		"tall"			"10"