diff --git a/pkgs/development/python-modules/pycontracts/default.nix b/pkgs/development/python-modules/pycontracts/default.nix
index 23633ce248d..cd9c054ddca 100644
--- a/pkgs/development/python-modules/pycontracts/default.nix
+++ b/pkgs/development/python-modules/pycontracts/default.nix
@@ -1,17 +1,17 @@
 { stdenv, buildPythonPackage, fetchPypi
-, nose, pyparsing, decorator, six }:
+, nose, pyparsing, decorator, six, future }:
 
 buildPythonPackage rec {
   pname = "PyContracts";
-  version = "1.8.3";
+  version = "1.8.6";
 
   src = fetchPypi {
     inherit pname version;
-    sha256 = "8e52c4ddbc015b56cc672b7c005c11f3df4fe407b832964099836fa3cccb8b9d";
+    sha256 = "8b6ad8750bbb712b1c7b8f89772b42baeefd35b3c7085233e8027b92f277e073";
   };
 
   buildInputs = [ nose ];
-  propagatedBuildInputs = [ pyparsing decorator six ];
+  propagatedBuildInputs = [ pyparsing decorator six future ];
 
   meta = with stdenv.lib; {
     description = "Allows to declare constraints on function parameters and return values";