diff --git a/pkgs/development/python-modules/python-jose/default.nix b/pkgs/development/python-modules/python-jose/default.nix
index 4eb2daaf26dc..14daecab4db8 100644
--- a/pkgs/development/python-modules/python-jose/default.nix
+++ b/pkgs/development/python-modules/python-jose/default.nix
@@ -25,6 +25,11 @@ buildPythonPackage rec {
     py.test
   '';
 
+  postPatch = ''
+    # File says it's utf-8 so instead of relying on the environment, fix the decoding when reading.
+    substituteInPlace setup.py --replace "open('README.md')" "open('README.md',encoding='utf-8')"
+  '';
+
   propagatedBuildInputs = [ future six ecdsa rsa ];
 
   meta = with stdenv.lib; {