diff --git a/pkgs/development/python-modules/claripy/default.nix b/pkgs/development/python-modules/claripy/default.nix
index 9816ff3782b3..b16505771492 100644
--- a/pkgs/development/python-modules/claripy/default.nix
+++ b/pkgs/development/python-modules/claripy/default.nix
@@ -8,6 +8,7 @@
 , pysmt
 , pythonOlder
 , pytestCheckHook
+, six
 , z3
 }:
 
@@ -36,6 +37,7 @@ buildPythonPackage rec {
   checkInputs = [
     nose
     pytestCheckHook
+    six
   ];
 
   postPatch = ''