diff --git a/pkgs/by-name/pi/pixi-pack/package.nix b/pkgs/by-name/pi/pixi-pack/package.nix
index 48ace993870c..0e0c25adb379 100644
--- a/pkgs/by-name/pi/pixi-pack/package.nix
+++ b/pkgs/by-name/pi/pixi-pack/package.nix
@@ -26,7 +26,7 @@ rustPlatform.buildRustPackage (finalAttrs: {
   nativeBuildInputs = [ pkg-config ];
 
   # Needed to get openssl-sys to use pkgconfig.
-  OPENSSL_NO_VENDOR = 1;
+  env.OPENSSL_NO_VENDOR = 1;
 
   # Tests require downloading artifacts from conda.
   doCheck = false;