diff --git a/pkgs/by-name/kr/krill/package.nix b/pkgs/by-name/kr/krill/package.nix
index a743be1f5f6a..909994f31062 100644
--- a/pkgs/by-name/kr/krill/package.nix
+++ b/pkgs/by-name/kr/krill/package.nix
@@ -24,7 +24,7 @@ rustPlatform.buildRustPackage rec {
   nativeBuildInputs = [ pkg-config ];
 
   # Needed to get openssl-sys to use pkgconfig.
-  OPENSSL_NO_VENDOR = 1;
+  env.OPENSSL_NO_VENDOR = 1;
 
   # disable failing tests on darwin
   doCheck = !stdenv.hostPlatform.isDarwin;