diff --git a/pkgs/development/tools/bashate/default.nix b/pkgs/development/tools/bashate/default.nix
index 31714db5c893..f46e9667cbef 100644
--- a/pkgs/development/tools/bashate/default.nix
+++ b/pkgs/development/tools/bashate/default.nix
@@ -8,6 +8,7 @@
 , pytestCheckHook
 , pythonOlder
 , setuptools
+, testtools
 }:
 
 buildPythonApplication rec {
@@ -30,6 +31,7 @@ buildPythonApplication rec {
     fixtures
     mock
     pytestCheckHook
+    testtools
   ];
 
   pythonImportsCheck = [ "bashate" ];