diff --git a/pkgs/overlay.nix b/pkgs/overlay.nix
index 2668d18..d327dd3 100644
--- a/pkgs/overlay.nix
+++ b/pkgs/overlay.nix
@@ -1,4 +1,4 @@
 final: prev: {
   think-gtcm = final.callPackage ./think-gtcm.nix { };
-  think-backend-gtcm = final.callPackage ./think-backend-gtcm.nix { };
+  think-backend-gtcm = final.callPackage ./think-backend-gtcm.nix { php = final.php83; };
 }
diff --git a/pkgs/think-backend-gtcm.nix b/pkgs/think-backend-gtcm.nix
index 53bed53..5deafb4 100644
--- a/pkgs/think-backend-gtcm.nix
+++ b/pkgs/think-backend-gtcm.nix
@@ -17,5 +17,5 @@ php.buildComposerProject2 (finalAttrs: {
   inherit src;
 
   composerStrictValidation = false;
-  vendorHash = "";
+  vendorHash = "sha256-eXm1x3E9KHWojaT2RU4inMdZqQVcWdLCKlvzhOlIZrc=";
 })