diff --git a/pkgs/development/python-modules/cozy/default.nix b/pkgs/development/python-modules/cozy/default.nix
index 0feca2773b37..7515891456e9 100644
--- a/pkgs/development/python-modules/cozy/default.nix
+++ b/pkgs/development/python-modules/cozy/default.nix
@@ -1,4 +1,4 @@
-{ buildPythonPackage, fetchFromGitHub, lib,
+{ buildPythonPackage, isPy3k, fetchFromGitHub, lib,
   z3, ply, python-igraph, oset, ordered-set, dictionaries }:
 
 buildPythonPackage {
@@ -29,6 +29,8 @@ buildPythonPackage {
     $out/bin/cozy --help
   '';
 
+  disabled = !isPy3k;
+
   meta = {
     description = "The collection synthesizer";
     homepage = https://cozy.uwplse.org/;