diff --git a/package/default.nix b/package/default.nix
index a300c5b0..96e3e1cb 100644
--- a/package/default.nix
+++ b/package/default.nix
@@ -25,11 +25,10 @@
       rev = "6ff3b71e3705e0d4081a51c21ca0379e869ba5fb";
       hash = "sha256-wC/2rAsSDO83UITaFhtaf3do3aaOAko4gnKUOzwURc8=";
     };
-    cargo = self.lib.cargoToml src;
   in
     buildPgrxExtension pkgs {
-      pname = cargo.package.name;
-      version = cargo.package.version;
+      pname = "pg_smtp_client";
+      version = "0.2.0";
   
       inherit src postgresql;
   
diff --git a/test/package/default.nix b/test/package/default.nix
index 05dd9387..5603c82c 100644
--- a/test/package/default.nix
+++ b/test/package/default.nix
@@ -1,4 +1,9 @@
 { system, inputs, self, pkgs }:
+let
+  smtpPackages = map
+    (version: self.packages.${system}."pg-${version}-ext-smtp-client")
+    [ "15" "16" "17" ];
+in
   (import ./migrator      { inherit system inputs self pkgs; }) //
   (import ./hemar         { inherit system inputs self pkgs; }) //
   (import (./. + "/sentinèlla") { inherit system inputs self pkgs; }) //
@@ -7,4 +12,12 @@
   (import ./with-attic-cache { inherit system inputs self pkgs; }) //
   (import ./element-web   { inherit system inputs self pkgs; }) //
   (import ./linux-devshell { inherit system inputs self pkgs; }) //
-  (import ./windows-devshell { inherit system inputs self pkgs; })
+  (import ./windows-devshell { inherit system inputs self pkgs; }) //
+  {
+    pg-smtp-client-metadata =
+      assert builtins.all (package: package.pname == "pg_smtp_client") smtpPackages;
+      assert builtins.all (package: package.version == "0.2.0") smtpPackages;
+      pkgs.runCommand "pg-smtp-client-metadata" {} ''
+        touch "$out"
+      '';
+  }