diff --git a/pkgs/development/libraries/grpc/default.nix b/pkgs/development/libraries/grpc/default.nix
index 346d04390c37..e24967eb30f1 100644
--- a/pkgs/development/libraries/grpc/default.nix
+++ b/pkgs/development/libraries/grpc/default.nix
@@ -3,13 +3,13 @@
 }:
 
 stdenv.mkDerivation rec {
-  version = "1.34.0"; # N.B: if you change this, change pythonPackages.grpcio-tools to a matching version too
+  version = "1.34.1"; # N.B: if you change this, change pythonPackages.grpcio-tools to a matching version too
   pname = "grpc";
   src = fetchFromGitHub {
     owner = "grpc";
     repo = "grpc";
     rev = "v${version}";
-    sha256 = "0kipk26kg2x06mrkhb74k8vk5cn4mr89kw1f9mb04n616wkxjyxy";
+    sha256 = "0p6si9i0gg885ag2x87a7jyzhgd5lhx2bh2vjj2ra1jn6y3vg6qk";
     fetchSubmodules = true;
   };
   patches = [
diff --git a/pkgs/development/python-modules/grpcio-tools/default.nix b/pkgs/development/python-modules/grpcio-tools/default.nix
index efae4b102d44..629c51071abd 100644
--- a/pkgs/development/python-modules/grpcio-tools/default.nix
+++ b/pkgs/development/python-modules/grpcio-tools/default.nix
@@ -1,12 +1,12 @@
-{ lib, stdenv, buildPythonPackage, fetchPypi, protobuf, grpcio, setuptools }:
+{ lib, buildPythonPackage, fetchPypi, protobuf, grpcio, setuptools }:
 
 buildPythonPackage rec {
   pname = "grpcio-tools";
-  version = "1.34.0";
+  version = "1.34.1";
 
   src = fetchPypi {
     inherit pname version;
-    sha256 = "db5a6f0130256d534cbe35eab37d37a448d96f4fd736e5051c6be1aee49cea1d";
+    sha256 = "b411f36748f4ead33411544d785e37825598bbb8abbe79eca422e395be5a3d08";
   };
 
   outputs = [ "out" "dev" ];
@@ -18,6 +18,8 @@ buildPythonPackage rec {
   # no tests in the package
   doCheck = false;
 
+  pythonImportsCheck = [ "grpc_tools" ];
+
   meta = with lib; {
     description = "Protobuf code generator for gRPC";
     license = licenses.asl20;