diff --git a/flake.lock b/flake.lock
index 1e6d6ee..abb3bb5 100644
--- a/flake.lock
+++ b/flake.lock
@@ -16,9 +16,26 @@
         "type": "github"
       }
     },
+    "nixpkgs-for-php": {
+      "locked": {
+        "lastModified": 1670538458,
+        "narHash": "sha256-mvKmBkdlhzsMBtnzYXjYn08EGw9rFBEE9hp4Uqgol1Q=",
+        "owner": "nixos",
+        "repo": "nixpkgs",
+        "rev": "99ec06122f481588abafd91f2710d80a5320efe6",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nixos",
+        "ref": "nixos-22.05",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
     "root": {
       "inputs": {
-        "nixpkgs": "nixpkgs"
+        "nixpkgs": "nixpkgs",
+        "nixpkgs-for-php": "nixpkgs-for-php"
       }
     }
   },
diff --git a/flake.nix b/flake.nix
index 15e5138..925d8a4 100644
--- a/flake.nix
+++ b/flake.nix
@@ -1,11 +1,13 @@
 {
   inputs = {
     nixpkgs.url = "github:nixos/nixpkgs/nixos-22.11";
+    nixpkgs-for-php.url = "github:nixos/nixpkgs/nixos-22.05";
   };
 
   outputs =
     { self
     , nixpkgs
+    , nixpkgs-for-php
     , ...
     }@inputs:
     let
@@ -20,15 +22,17 @@
             pkgs = import nixpkgs {
               inherit system;
             };
+            phpPkgs = import nixpkgs-for-php {
+              inherit system;
+            };
 
             phpEnv = pkgs.mkShell {
               name = "gh-event-forwarder";
               buildInputs = with pkgs; [
                 nix-prefetch-git
-                php
-                phpPackages.composer
+                phpPkgs.php
+                phpPkgs.phpPackages.composer
                 git
-                php
                 curl
                 bash
               ];
@@ -85,6 +89,10 @@
             inherit system;
           };
 
+          phpPkgs = import nixpkgs-for-php {
+            inherit system;
+          };
+
           pkg = pkgs.rustPlatform.buildRustPackage {
             name = "ofborg";
             src = pkgs.nix-gitignore.gitignoreSource [ ] ./.;
@@ -142,7 +150,7 @@
             test -e $out/bin/evaluation_filter
           '';
 
-          ofborg.php = import ./php { inherit pkgs; };
+          ofborg.php = import ./php { pkgs = phpPkgs; };
         });
 
       hydraJobs = {