diff --git a/pkgs/development/python-modules/flatbuffers/default.nix b/pkgs/development/python-modules/flatbuffers/default.nix
index db0405cc34d1..3c36197b7f3d 100644
--- a/pkgs/development/python-modules/flatbuffers/default.nix
+++ b/pkgs/development/python-modules/flatbuffers/default.nix
@@ -13,7 +13,7 @@ buildPythonPackage rec {
 
   # flatbuffers needs VERSION environment variable for setting the correct
   # version, otherwise it uses the current date.
-  VERSION = version;
+  env.VERSION = version;
 
   pythonImportsCheck = [ "flatbuffers" ];