diff --git a/pkgs/by-name/ju/julefmt/package.nix b/pkgs/by-name/ju/julefmt/package.nix
index c8902c3e3f73..10753f2d3bfa 100644
--- a/pkgs/by-name/ju/julefmt/package.nix
+++ b/pkgs/by-name/ju/julefmt/package.nix
@@ -18,7 +18,7 @@ clangStdenv.mkDerivation (finalAttrs: {
 
   nativeBuildInputs = [ julec.hook ];
 
-  JULE_OUT_NAME = "julefmt";
+  env.JULE_OUT_NAME = "julefmt";
 
   meta = {
     description = "Official formatter tool for the Jule programming language";