diff --git a/pkgs/by-name/re/reaction/package.nix b/pkgs/by-name/re/reaction/package.nix
index 47d6c3c820cf..84de0d125552 100644
--- a/pkgs/by-name/re/reaction/package.nix
+++ b/pkgs/by-name/re/reaction/package.nix
@@ -26,8 +26,8 @@ in buildGoModule {
   ];
 
   postBuild = ''
-    gcc helpers_c/ip46tables.c -o ip46tables
-    gcc helpers_c/nft46.c -o nft46
+    $CC helpers_c/ip46tables.c -o ip46tables
+    $CC helpers_c/nft46.c -o nft46
   '';
 
   postInstall = ''