diff --git a/flake.nix b/flake.nix
index 5ee8052..16e32bc 100644
--- a/flake.nix
+++ b/flake.nix
@@ -73,6 +73,7 @@
           "sourcemod-plugin-who"
           "sourcemod-plugin-afk"
           "sourcemod-plugin-demostf"
+          "sourcemod-plugin-properpregame"
         ]
         // {
           test = pkgs:
@@ -83,7 +84,7 @@
               sourcemod = true;
               plugins = with pkgs; [
                 sourcemod-plugin-soap-tf2dm
-                sourcemod-plugin-demostf
+                sourcemod-plugin-properpregame
                 srctvplus
               ];
             };
diff --git a/nix/sourcemod/plugins/builder/plugin.nix b/nix/sourcemod/plugins/builder/plugin.nix
index dfe25b8..5d78c3e 100644
--- a/nix/sourcemod/plugins/builder/plugin.nix
+++ b/nix/sourcemod/plugins/builder/plugin.nix
@@ -13,6 +13,7 @@ lib.extendMkDerivation {
     installIncludes ? [],
     runtimeInputs ? [],
     src,
+    passthru ? {},
     ...
   }: let
     inherit (lib) concatStringsSep map length optionalString;
@@ -49,6 +50,10 @@ lib.extendMkDerivation {
       runHook postInstall
     '';
 
-    passthru.runtimeInputs = runtimeInputs;
+    passthru =
+      passthru
+      // {
+        runtimeInputs = runtimeInputs;
+      };
   };
 }
diff --git a/nix/sourcemod/plugins/overlay.nix b/nix/sourcemod/plugins/overlay.nix
index 7195796..8d227af 100644
--- a/nix/sourcemod/plugins/overlay.nix
+++ b/nix/sourcemod/plugins/overlay.nix
@@ -16,4 +16,5 @@ final: prev: {
   sourcemod-plugin-who = final.callPackage ./who.nix {};
   sourcemod-plugin-afk = final.callPackage ./afk.nix {};
   sourcemod-plugin-demostf = final.callPackage ./demostf.nix {};
+  sourcemod-plugin-properpregame = final.callPackage ./properpregame.nix {};
 }
diff --git a/nix/sourcemod/plugins/properpregame.nix b/nix/sourcemod/plugins/properpregame.nix
new file mode 100644
index 0000000..2fd610d
--- /dev/null
+++ b/nix/sourcemod/plugins/properpregame.nix
@@ -0,0 +1,33 @@
+{
+  fetchFromGitHub,
+  mkSourcemodPlugin,
+  nix-update-script,
+  sourcemod-plugin-soap-tf2dm,
+}:
+mkSourcemodPlugin (finalAttrs: {
+  pname = "sourcemod-plugin-properpregame";
+  version = "0-unstable-2020-06-06";
+  src = fetchFromGitHub {
+    owner = "AJagger";
+    repo = "ProperPregame";
+    rev = "7698dabc7948f06d4821fc784c665ec4d8cacb5d";
+    hash = "sha256-UfFmIsukf+v62317vqclMhT3zKLbL/qNrLJC296/8vw=";
+  };
+
+  plugins = ["addons/sourcemod/scripting/properpregame.sp"];
+  runtimeInputs = [sourcemod-plugin-soap-tf2dm];
+
+  postInstall = ''
+    mkdir -p $out/cfg/sourcemod
+    cp cfg/sourcemod/* $out/cfg/sourcemod
+  '';
+
+  passthru = {
+    updateScript = nix-update-script {
+      extraArgs = [
+        "--flake"
+        "--version=branch"
+      ];
+    };
+  };
+})