diff --git a/pkgs/development/python-modules/google-cloud-spanner/default.nix b/pkgs/development/python-modules/google-cloud-spanner/default.nix
index e5e32526a1cb..1fdf98d3baa3 100644
--- a/pkgs/development/python-modules/google-cloud-spanner/default.nix
+++ b/pkgs/development/python-modules/google-cloud-spanner/default.nix
@@ -1,16 +1,17 @@
 { lib
 , buildPythonPackage
 , fetchPypi
-, grpc-google-iam-v1
 , google-cloud-core
 , google-cloud-testutils
+, grpc-google-iam-v1
 , libcst
 , mock
 , proto-plus
-, pytestCheckHook
+, protobuf
 , pytest-asyncio
-, sqlparse
+, pytestCheckHook
 , pythonOlder
+, sqlparse
 }:
 
 buildPythonPackage rec {
@@ -28,16 +29,22 @@ buildPythonPackage rec {
   propagatedBuildInputs = [
     google-cloud-core
     grpc-google-iam-v1
-    libcst
     proto-plus
+    protobuf
     sqlparse
-  ];
+  ] ++ google-api-core.optional-dependencies.grpc;
+
+  passthru.optional-dependencies = {
+    libcst = [
+      libcst
+    ];
+  };
 
   checkInputs = [
     google-cloud-testutils
     mock
-    pytestCheckHook
     pytest-asyncio
+    pytestCheckHook
   ];
 
   preCheck = ''